U.S. ORDNANCE – Small Arms Defense Journal

Torturing the Mk19 Mod 3: Performing the Full Mil-Spec Testing Protocol

Dan Shea — Tue, 19 Mar 2024 13:00:00 +0000

Since 2016, U.S. Ordnance has been the sole supplier of the U.S. Model MK19 Mod 3 and Mod 4 machine guns to U.S. military and other government agency end-users. In 2022, they were issued the NSN as sole supplier with an IDIQ contract of up to $50m. As we go to press, they are in the first article testing phase of the contract, and we were allowed to participate in the testing. We previously reported on Phase I, and now we report on Phase II here. It’s an extensive inspection and live firing test.

Since U.S. Ordnance received the NSN and contract, they must perform “first article” inspection and testing. There are more than 186 parts inspections that must be accomplished. Each one must meet the military standards for production. There is also a testing protocol called for in MIL-G-70790 (AR), the Military Specification for Gun, Machine, 40mm MK19 Mod 3, which must be strictly adhered to and passed with government inspectors viewing. In the previous article, we reviewed the relevant first parts of the testing we observed. Now it’s time to go live, but there are more checks to perform before we can start.

MK19 Mod 3 Specifications

Caliber	40x53mm
Weight	77.6 lb. (35.2kg) empty
Length	43.1 in. (1090mm)
Width	9.46 in. (240.4mm)
Barrel Length	16.25 in. (413mm) (Removable)
Muzzle Velocity	750-790 fps (230-240 m/s)
Effective Firing Range	1,500m (1,600 yards)
Maximum Firing Range	2,212m (2,419 yards)
Feed system	32 or 48 grenade belts in metal can, M16A2 link

In section 3.3 of the Mil-Spec, gun sights and bore calibration are checked. The wedge optic mount on the right side in the MWO has to be perfect for calibration, which we did check. Then, in 3.4 and 3.5, it’s an ammunition compatibility check to ensure all the various 40x53mm rounds will chamber and fire. Done. Then, as stated in 3.5.1, “Proof Testing: The machine gun shall withstand the firing of one M385A1 40mm cartridge without any evidence of part failure, deformation, or loosening.” Done.

The M385A1 round has a one-piece solid aluminum projectile with a rotating band in an M169 cartridge case. The propellant is M2 (4.2g, 0.15 oz.). The primer is an FED 215 percussion-type. The ogive of the M385 series matches the shape of the M430/A1 HEDP projectile, which has 45g (1.61 oz.) of Comp A5 explosive, a shaped charge with copper liner, and a pre-fragmented body. It’s just the ogive that matches. The M385 series frequently is indented at center, which is weight lightening to match the weight of the M430 round. The M385A1 uses M16A2 links only (The M385 can use either M16A1 or A2).

There are protocols, as mentioned. Firing must be done in a proper, specified cadence to allow proper cooling periods, simulating the long life of a MK19 Mod 3 in service. Cleaning intervals must be followed, as well as inspections, including some testing that might appear redundant, but is necessary to achieve the full results of the test.

Benchmarks in the MK19 Mod 3 MIL-Spec First Article Acceptance Test

(SADJ covered many of these items in the first article in this series, it is online at www.sadefensejournal.com, if you would like to refer to it).

Spoiler Alert: U.S. Ordnance’s MK19 Mod 3 program has passed all of the MIL-Spec testing and is in the third phase. They are the only source of U.S.-made MK19 Mod 3 machine guns accepted by the U.S. military.

Pre-Firing Inspection There are 19 points to cover in this visual inspection.
Ammunition Compatibility Check This is done with a variety of issue rounds supplied by the customer. There are 12 steps in this process, covered in our first article.
Gun Sight and Bore Calibration Check There are 12 steps in this process, covered in this article.
Proof Inspection This is a 3-part inspection involving firing on round of M385A1 ammunition.
Firing Mode This is a test in 8 parts of the firing mechanism including the solenoid remote firing.
Belt Pull A four-part test, done with free hanging 28-round belts, in two to four round bursts. We performed this test in the first article, but again throughout the second testing.
Cycling Rate of Fire Measured with 10-round belts. Interestingly, the string of rounds is not averaged for rate of fire but measured individually to meet the required rate.
Trunion Load Performed in the test report in this article.
Accuracy At 1000m, a 14m target is set. Firing is done in 2-3 round bursts and all rounds must hit the target. Performed both test days we were there for.
Post-Firing Cleaning At all times that are called for, a full inspection is done for proper cleaning and reassembly. Parts are inspected according to 9 focus points.
Interchangeability In the first article we did, we covered some of this, but the further full testing has more of this, and a special station is set up.
Reliability The longest part of the test, It begins with firing 192 rounds, and repeating it after rounds 152, 2304, 3456, 4608, and 5760. It is a specific cadence, intended to show any dispersion changes, or other issues.
Full Cleaning and Inspection Specified at every 2,304 rounds. The guns are completely disassembled, visually and magnetic particle inspected, cleaned, and properly lubricated. Parts to lubricate are the bolt, barrel, firing pin cover, firing pin, bolt sear, firing pin sear, receiver, lock plate, and feed tray.

Graflex Inc, cage code IDBZ2, makes the borescope used in the bore sighting process. Model 1-1001-BR, W56HZV-05-G-005 is the model. This scope is used on the 50 BMG machine guns, as well as on the MK19 40mm guns. The lower spud is for the .50 caliber guns, the upper is for the 40mm, like the MK19. (Dan Shea)

The special bore sighting MK19 target is placed at the other end of the test tunnel, the fixtured MK19 has the scope inserted and zeroed in, and the sights are calibrated to match. This must be done before the firing protocol has started. (Dan Shea)

Measuring, markings, finish depths, examination of every part were all done, Now it’s time to put the hammer down on the gun. Again, we had firing cadences that must be followed, with parts changes and interchanges as we go. The ammunition is piled up and the guns are in the rack. (Dan Shea)

Measuring, markings, finish depths, examination of every part were all done, Now, it’s time to put the hammer down on the gun. Again, we had firing cadences that must be followed, with parts changes and interchanges as we go. The ammunition is piled up and the guns are in the rack. (Dan Shea)

An area for disassembly, switching out parts, and reassembly is prepared. There are bins for each part, and when the test guns are disassembled, they parts go in the bins and are randomly reassembled. (Dan Shea)

In the disassembly area, photographic guides are on the wall to detail what level disassembly must be done at this station. (Dan Shea)

Each gun is tracked in the disassembly area with this chart detailing what goes next for each MK19. (Dan Shea)

Every time a MK19 has the bolt disassembled, there are about 12-15 replaceable parts that must be replaced each time. There are nylon head screws, helical springs, plastic discs, and tie wire that must be re-tied. It’s a time-consuming process and called for in the Mil-Spec. (Dan Shea)

The basic tools of disassembly; top is the MK19 multi-tool, bottom is a specially designed prybar that operators and armorers favor for many tasks, specifically removing rounds on the bolt face. (Dan Shea)

Fired MK19 Mod 3 on the disassembly table, ready for a stage one inspection. (Dan Shea)

Basic assemblies that will be inspected at short interval. (Dan Shea)

After the proof testing called for in 3.6, magnetic particle inspection (MPI) is performed. This is also called for all throughout the testing. Parts are sent to be tested at intervals. Generally, this is called “Magnafluxing” after the manufacturer usually associated with the process. It’s a non-destructive process, and in the case of U.S. Ordnance, they use a “wet” system which is ideal for production needs. In this wet system, a petroleum based “suspension vehicle”, basically a light oil, has a specified quantity of fluorescent magnetic particles added to it (suspended in it). The formula is pretty standard in this use; Magnaglo 14A particles in Carrier II liquid. (Dan Shea)

After the top cover has been reassembled, proper lubrication is applied. One thing about MK19s, they do not like CLP. It gums them up, badly. It’s actually forbidden to use it in MK19s. LSA is called for in normal use. Most of us in the field use TW-25b, the same Teflon-based grease that we use in aerospace and M134 Miniguns. We also don’t mix lubrication. It’s TW-25b or something else. (Dan Shea)

Looking up inside the cover at the very bottom in this picture, a helical spring is evident. This spring must be proper for the presentation of the round to the bolt face. Each time the system is disassembled, this must be checked. (Dan Shea)

The feed adjustment tool is placed in the feed tray, as shown. It will now be visible from the ogive hole in the receiver front. (Dan Shea)

With the tool in position, the bolt is retracted and held open. (Dan Shea)

The white lines are on each other, lined up within tolerances for proper feeding. If they do not line up, adjustments must be made. It is expected that through most of the firing these will not get out of line during disassembly. (Dan Shea)

During the test, after reassembly, to cycle the MK19, four dummy rounds are placed in the feed tray, female link first. (Dan Shea)

When the bolt is retracted, visual inspection should show a round on the bolt face as seen through the charging handle slot. (Dan Shea)

Looking down through the top of the open MK19, a dummy round can see being held on the bolt face. The MK19 tool is being used to pry it downward off the bolt face through the right-hand charging slot. (Dan Shea)

The outdoor section of live firing was done at the local range U.S. Ordnance owns. This picture is after the first can of ammo is fired. Some firing was also done from a HUMVEE mount. (Dan Shea)

The majority of the ammunition is fired inside a special test building that has a unique water trap for the rounds to be fired into. The water is filtered and recycled into the trap; the projectiles are automatically removed from the container with a conveyor system. The MK19 is held this high above ground, as part of the belt pull protocols calling for 28 hanging rounds in the test. Belt pull strength is constantly monitored to see if there is any degradation. (Dan Shea)

A custom mount was made in-house by U.S. Ordnance, and it allows the use of the electric firing solenoid system, which is designed to make the cadence of firing easier to perform. (Dan Shea)

A better view of the custom firing platform. (Dan Shea)

The mount shown here is a special mount custom made to the government specification for the test. (Dan Shea)

The Kistler Force meter is a very expensive and sensitive piece of equipment, yet it is built to handle the recoil forces of larger forces than will be in this test. (Dan Shea)

In Section 4.5.8 “Trunnion Load”

A. For First Article Inspection, this test shall be performed concurrently with the belt pull test.
B. Mount a Quartz Force Link Cell Kistler Model 9362 with a Charge Amplifier Model 504E and a Filter Model 545A (Or Equivalent) directly below the receiver, below the locking pin, integral with the mount and in alignment with the receiver buffers.
C. Record a time-load trace of recoil using a Honeywell Visicorder Modl 1858 with a TCD (tape compatible differential) Amplifier Model 1887, or approved alternate equipment.
D. Trunion load forces are to be measured at the mounting point. The last three (3) rounds of the belt fired shall be discounted.

The mount shown here is a special mount custom made to the government specification for the test. The Kistler Force meter is a very expensive and sensitive piece of equipment, yet it is built to handle the recoil forces of larger forces than will be in this test. The reason for testing during the belt-pull test are based on finding variations in the side weight of the belt, and as the belt lightens the forces will change. This data will be valuable to see the consistency of the construction. After this first article test, the trunnion load tests will be less frequent but based purely on the single rounds fired.

At various times in the process, sectioning of barrels is called for, in order to judge throat, bore, and muzzle erosion. Gauges are used for most of this, but thin slices must be made in order to measure the rifling depth, as well as chrome depth. The barrel grooves must be checked for height all through samples of the production barrels. Here, an extremely thin shim (0.030-0.040in.) is cut cross-sectionally from the middle of the barrel and the consistency and depth of grooves related to lands are checked, as well as the finish depth. The chrome should be 0.002in. thick. Obviously, these are destructive tests and done on random barrels during the specification match testing. (Dan Shea)

After test-cycling the MK19 with dummy rounds, this is what they look like. (Dan Shea)

Note that the links are de-linked and pushed to the rear. In this closeup, the male and female end of the links are evident. (Dan Shea)

After test-cycling the MK19 with dummy rounds, this is what they look like. Note that the links are de-linked and pushed to the rear. In the closeup, the male and female end of the links are evident.

The male end must be pulled out of the female, to the rear. Thus, when a can of ammunition is first opened, the first round will present with a female end of the link to feed into the feed tray. On cocking, the round is pulled to the rear, then slammed forward into the barrel, pushing the single link rearward on the body of the casing, and ejecting it. When fed into the HK GMG machine gun, because it pushes through forward, the belt must be presented opposite, with the male link into the feed first. This requires taking the belts out of the can before using and reversing the belt.

In U.S. Ordnance’s instructor classroom, they’ve made a custom factory cutaway of the MK19 Mod 3 as a training aid. We are curious if these will be available for contract sales. (Dan Shea)

In U.S. Ordnance’s instructor classroom, they’ve made a custom factory cutaway of the MK19 Mod 3 as a training aid. We are curious if these will be available for contract sales.

U.S. Ordnance’s custom factory cutaway of the MK19 Mod 3 as a training aid. (Dan Shea)

MK19 Mod 3: U.S. Ordnance Runs the Gauntlet

Dan Shea — Tue, 10 Oct 2023 13:00:00 +0000

Since 2016, U.S. Ordnance has been the sole supplier of the US Model MK19 Mod 3 and Mod 4 machine guns to U.S. military and OGA end users. In 2022, they were issued the NSN as sole supplier, with an IDIQ contract of up to $50 million. As we go to press, they are in first article testing on the contract, and we were allowed to participate in the testing, phase I. (Phase II will be reported on in the first issue of SADJ 2024, it’s an extensive live firing test).

MK19 Mod 3

Specifications

Caliber: 40x53mm
Weight: 77.6 lb. (35.2kg) empty
Length: 43.1 in. (1090mm)
Width: 9.46 in. (240.4mm)
Barrel Length: 16.25 in. (413mm) (Removable)
Muzzle Velocity: 750-790 fps (230-240 m/s)
Effective Firing Range: 1,500m (1,600 yards)
Maximum Firing Range: 2,212m (2,419 yards)
Feed system: either 32 or 48 grenade belts in metal can, M16A2 link.

Since U.S. Ordnance received the NSN and contract, there are now over 186 parts inspections that must be accomplished. Each one must meet the military standards for production. There is also a protocol testing called for in MIL-G-70790 (AR), the Military Specification for Gun, Machine, 40mm MK19 Mod 3, which must be strictly adhered to and passed with government inspectors viewing the proceedings. In this article, we’ll review relevant first parts of the testing we observed.

In section 3.3, gun sights and bore calibration are checked- the wedge optic mount on the right side in the MWO has to be perfect for calibration, which we did check. Then in 3.4 and 3.5, it’s an ammunition compatibility check to ensure all the various 40x53mm rounds will chamber and fire, done. In section 3.5.1 Proof Testing: “The machine gun shall withstand the firing of one M385A1 40mm cartridge without any evidence of part failure, deformation, or loosening.” Done. The M385A1 has a one-piece solid aluminum projectile with a rotating band, in an M169 cartridge case. The propellant is M2 (4.2g, (0.15 oz.)), the primer is an FED 215 percussion type. The ogive of the M385 series matches the shape of the M430/A1 HEDP projectile which has 45g (1.61 oz.) of Comp A5, a shaped charge with copper liner, and a pre-fragmented body. It’s just the ogive that matches, the M385 series frequently is indented at center, weight lightening to match the M430. The M385A1 uses M16A2 links only (the M385 can use either M16A1 or A2).

Rows of MK19 bare receivers in the process of getting all weldments done. Note the tracking papers – each part is tracked all through production.

While the receivers are still in the unfinished state, the dimensions are checked in every possible manner. Here, the receiver length is checked with a Trimos Mestra Touch height measuring instrument. This is one of the most accurate instruments that can be had in the market today. Mestra-touch has all the basic functions such as checking heights, depths, diameters and centerline distances, squareness deviation, angles and tolerance limits indication. In addition, the Mestra-Touch has a color touch screen and functions such as the two-coordinate system, programming of measuring sequences, statistical analysis of memorized values and display of environmental temperature. It can also record and convey the data to the computer system used in QC. Instruments like this are critical in tracking manufacturing process and especially, for government contracts like this one. The MK19 receiver is a difficult one to make, U.S. Ordnance has nailed the process, perfectly.

Once the receivers have been thoroughly checked, they go to Parkerizing; this is a three-step process. The first tank cleans the surfaces with a solvent solution, the second has the actual Parkerizing solution (a phosphoric solution), and is heated. The chemistry and temperatures in these tanks are critical and the contents are not mixed. The last process is clean water, that flows and cleans the solution from the surface and finalizes the finish. Finishes are up to 1-2 micrometers thick when done, depending on the spec.

After Parkerizing, more gauging is done before assembly starts.

Barrels are installed at the barrel station.

Bolt assemblies have been prepared, every part gauged, and assembled.

Final assembly is done at the production station. In section 3.6, Interchangeability, five guns were chosen, disassembled, parts mixed, then five guns were assembled from random parts, and gauging and testing were done. This was all a complete pass for the testing we did.

Section 3.7 Marking: Each machine gun and each part for which marking is prescribed shall be clearly marked in accordance with MIL-STD-130. Each receiver shall be identified with a serial number which shall be assigned by the procuring activity. The markings in this photo are the correct ones according to the MIL-STD. The barrel markings are as well, but parts like the barrel also receive a “PM” mark for “Proof” and “Magnetic Particle Tested” (See the M249 article in this issue for Magnaflux procedures).

Finished MK19 barrels waiting for assembly. As part of the MIL-STD, the grooves must be checked for height all through samples of the production barrels. Here, an extremely thin shim is cut cross-sectionally of the middle of the barrel, and the consistency and depth of grooves related to lands are checked, as well as finish depth. The cutaway barrel is for reference on the chamber and how the projectile is entering the grooves in the bore. Obviously, these are destructive tests and done on random barrels during the specification match testing.

MK19 pins waiting for individual review.

In Section 4.5.8 Trunnion Load, a. for First Article Inspection, this test shall be performed concurrently with the belt pull test. B. Mount a Quartz Force Link Cell Kistler Model 9362 with a Charge Amplifier Model 504E and a Filter Model 545A (Or Equivalent) directly below the receiver, below the locking pin, integral with the mount and in alignment with the receiver buffers. C. Record a time -load trace of recoil using a Honeywell Visicorder Modl 1858 with a TCD (tape compatible differential) Amplifier Model 1887, or approved alternate equipment. D. Trunion load forces are to be measured at the mounting point. The last three (3) rounds of the belt fired shall be discounted. The mount shown here is a special mount custom made to the government specification for the test. The Kistler Force meter is a very expensive and sensitive piece of equipment, yet it is built to handle greater recoil forces than it will measure in this test. The reason for testing during the belt-pull test is based on finding variations in the side weight of the belt, and as the belt lightens the forces will change. This data will be valuable to see the consistency of the construction. After this first article test, the trunnion load tests will be less frequent but based purely on single rounds fired.

40x53mm ammo piled up in anticipation.

In the next issue of Small Arms Defense Journal, we will be joining U.S. Ordnance for the full-tilt firing part of the test. The ammo is lined up, the testing fixtures are ready, and we’ll be doing cadenced endurance testing, temperature testing, belt-pull, cyclic rate of fire, angle of fire, firing modes, accuracy, reliability, and a host of other tests. The full trunnion load test will be done several times through the testing. Be sure to join us!

EDITORIAL SPECIAL: MACHINE GUNS

SADJ Staff — Thu, 17 Sep 2020 20:42:55 +0000

ARSENAL® JSCO, BULGARIA

MG-1M

The 7.62x54mm ARSENAL MG-1M machine guns are powerful automatic weapons, used as armament against enemy troops and firing points. The MG-1M design is specially intended and allows operation of the weapon in heavy climatic conditions, which are typical for the regions of the Middle East, Southeast Asia and Africa.

arsenal-bg.com

Caliber/Bore: 7.62x54mm
Barrel Length: 605mm
FFL Status: For American manufacturer
Type of Links: Integrated via joint springs
Rate of Fire: 650 RPM

ARSENAL® JSCO, BULGARIA

MG-M2

The 7.62x51mm ARSENAL MG-M2 machine gun is a powerful individual automatic weapon designed to be used against enemy troops, light armoured targets and aerial targets by firing in single and automatic fire mode.

arsenal-bg.com

Caliber/Bore: 7.62x51mm
Barrel Length: 545mm
FFL Status: For American manufacturer
Type of Links: Disintegrating metal belt, M13 type
Rate of Fire: 650 RPM

DILLON AERO

M134D 7.62×51 Minigun

The Dillon Aero M134D 7.62×51 Minigun is renowned worldwide for its reliability, speed and accuracy. With low recoil forces, a firing rate of 3,000 rounds per minute (RPM) and an effective range of 1,200m, the M134D’s offensive and defensive capabilities are unmatched in air, land and sea applications.

dillonaero.com

Caliber/Bore: 7.62x51mm
Barrel Length: 18in to 22in
FFL Status: Importer/Exporter
Type of Links: M13
Rate of Fire: Up to 4,000 RPM

DILLON AERO

503D

Dillon Aero introduced the 503D, our new .50-caliber Gatling gun. Weighing 84 pounds, firing 1,500 rounds per minute (RPM) with increased resistance to internal component damage, the 503D has applications on air, sea and land platforms. The 503D is lighter, faster and smarter than other .50-caliber Gatling guns.

dillonaero.com

Caliber/Bore: .50 BMG
Barrel Length:
FFL Status: Importer/Exporter
Type of Links: M9
Rate of Fire: Up to 1,500 RPM

FIGHTLITE INDUSTRIES

MCR® Dual Feed Upper M-LOK® (MCR-060)

The MCR® (Mission Configurable Rifle) belt-fed, upper receiver assembly is designed to interchange with standard AR/M4-type uppers and readily fits any MIL-SPEC lower receiver without permanent modification to the host lower and is rearward-compatible to AR-15/M16 models produced as early as 1963. Once installed, the patented MCR® upper receiver system can be user-configured in seconds without tools to adapt to virtually any mission profile. Standard features include: gas-piston operation for extreme reliability in adverse conditions; a 16.25-inch quick-change (3 seconds) barrel system; and a MIL-STD-1913 co-planar handguard with a rail-interface system for the mounting of optics and modern accessories. Spanning the capability range from the optic-ready carbine to a lightweight support rifle, the MCR® accepts standard box-type AR-15/M16 magazines or M27 linked ammunition.

fightlite.com

Caliber/Bore: 5.56x45mm NATO
Barrel Length: 16.25in quick-change barrel
FFL Status: N/A
Type of Links: M27 linked ammunition
Rate of Fire: N/A

FN AMERICA

FN® MK 48 MOD 1

The FN® MK 48 MOD 1 brings the extended range and greater penetration of the hard-hitting 7.62x51mm round in a lighter, more compact platform. The light and compact MK 48 MOD 1 incorporates improved receiver pins, a new gas block and a vented handguard with improved heat shield and three MIL-STD-1913 rails. The MK 48 MOD 1’s cold hammer-forged MIL-SPEC barrel has a hard-chromed bore for longer life and improved accuracy and serves as the mounting point for the carry handle. The receiver is formed steel and is equipped with a top-mounted MIL-STD-1913 optical rail. A hydraulic buffer greatly reduces recoil, helping the operator keep more rounds on target. The crossbolt safety and curved trigger help enhance operator control. Includes one spare barrel.

fnamerica.com

Caliber/Bore: 7.62×51 NATO
Barrel Length: 19.75in
FFL Status: N/A
Type of Links: NATO standard disintegrating link belt-fed
Rate of Fire: 730 RPM

FN HERSTAL

FN MINIMI® 7.62 MK3

The FN MINIMI® 7.62 Light Machine Gun is now of 3rd generation and ensures improved ergonomics and improved mobility.

fnherstal.com

Caliber/Bore: 7.62
Barrel Length: 16.61in
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 800 RPM

GENERAL DYNAMICS

Lightweight Medium Machine Gun (LWMMG)

The next generation Lightweight Medium Machine Gun (LWMMG) gives warfighters a distinct advantage in both extended and close-in fighting. Eliminating the gap between 7.62mm and .50 caliber weapons, the LWMMG utilizes the highly efficient .338 Norma Magnum cartridge to offer increased accuracy and lethality while extending the battlespace out to an impressive 1,700m. At 1,000m, the LWMMG is capable of defeating Level III body armor and incapacitating soft-skinned vehicles by delivering over 1,900 foot pounds of energy to the target—more than four times the terminal effect of the 7.62mm NATO cartridge.

gd-ots.com

Caliber/Bore: .338
Barrel Length: 24in
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 500 RPM

HECKLER & KOCH

MG4

The MG4 is a lightweight, compact machine gun of high firepower, with a goal of being carried by one soldier and guarantee full mobility in difficult terrain and also in the urban environment. The MG4 offers the latest technological advances and provides unmatched performance characteristics: Due to its low recoil, the shot is readily controllable, giving high-target precision. Its great combat effectiveness and range, optimal rate of fire and simple handling makes it a weapon unlike any other.

heckler-koch.com

Caliber/Bore: 5.56mmx45
Barrel Length: 450mm
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 830+120 RPM

HECKLER & KOCH

MG5

As the successor of the MG3, the MG5 opens a new era of universal belt-fed 7.62mmx51 machine guns. The gas-operated MG5 offers an intelligent and contemporary build standard, with numerous technical and ergonomic innovations. The mounting interface of the MG5 is compatible with MG3 mounts and tripods already in service. The universal MG5 can be used by dismounted infantry in the ground role, as well as for air defence or as a vehicle mounted/co axial machine gun.

heckler-koch.com

Caliber/Bore: 7.62mmx51 NATO
Barrel Length: 550mm
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 680 / 740 / 800 RPM

IWI–ISRAEL WEAPON INDUSTRIES

NEGEV 5.56 LMG

The 5.56x45mm NEGEV is a robust and reliable Light Machine Gun (LMG), deployed by the IDF in Israel and by military entities worldwide. The NEGEV has a powerful target acquisition and accurate performance for the modern battlefield. It is exceptionally lightweight (less than 8kg) and can be operated safely under adverse and extreme environmental conditions.

iwi.net

Caliber/Bore: 5.56x45mm
Barrel Length: 460mm (18in) or 330mm (13in)
FFL Status: N/A
Type of Links: Fed by belt, assault drum or by NATO magazine
Rate of Fire: 850–1,050 RPM (magazine/belt) / 950–1,050 RPM (belt)–extreme conditions

IWI–ISRAEL WEAPON INDUSTRIES

NEGEV NG-7 LMG

The NEGEV NG-7 is the only 7.62x51mm LMG weighing less than 8kg with a semiautomatic mode enabling its safe use in Close Quarter Battle (CQB). The NG-7 is a powerful LMG with superior features such as precision, accuracy, reliability and enhanced human ergonomics and is battle-proven under adverse and extreme environmental conditions.

iwi.net

Caliber/Bore: 7.62x51mm
Barrel Length: 508mm (20in) or 420mm (16.5in)
FFL Status: N/A
Type of Links: Fed by belt, assault drum or by NATO magazine
Rate of Fire: 600–750 RPM (position 1 & 2)

OHIO ORDNANCE WORKS, INC. (OOW)

OOW240P (Patrol)

OOW manufactures light (249), medium (240) and heavy (M2) machine guns for customers in 43 countries worldwide. Our newest “Patrol” models of our “240” product line feature reduced weight while allowing more operator customization and greatly increasing the ability to accurately fire these weapons from the shoulder.

oowinc.com

Caliber/Bore: 7.62mm
Barrel Length: 19.5in
FFL Status: Type 10/11 Manufacturer/Importer/Exporter
Type of Links: M13
Rate of Fire: 650–750 RPM

OHIO ORDNANCE WORKS, INC. (OOW)

OOW249P (Patrol)

OOW manufactures light (249), medium (240) and heavy (M2) machine guns and has customers in 43 countries worldwide. Our newest “Patrol” models of our “249” product line feature reduced weight while allowing more operator customization and greatly increasing the ability to accurately fire these weapons from the shoulder.

oowinc.com

Caliber/Bore: 5.56mm
Barrel Length: 13in
FFL Status: Type 10/11 Manufacturer/Importer/Exporter
Type of Links: M27
Rate of Fire: 750–1,000 RPM

SIG SAUER, INC.

MG 338

The SIG SAUER MG 338 machine gun is a belt-fed, lightweight medium machine gun weighing under 20 pounds, chambered in .338 Norma Mag. The MG 338 features a short-stroke, gas-piston system and a proprietary recoil mitigation system, with a free-floating, quick-change barrel; ambidextrous controls; switchable feed tray; charging handle that can be alternated to either side depending on operator preference; and as a modern, multi-caliber, modular system, the new SIG MG 338 is easily convertible to 7.62×51 caliber.

sigsauer.com

Caliber/Bore: .338 Norma Magnum
Barrel Length: 20in
FFL Status: N/A
Type of Links: Disintegrating metal links
Rate of Fire: N/A

SIG SAUER, INC.

NGSW-AR MG 6.8

The primary objectives set forth by the U.S. Army for the NGSW-AR was a weapon with the firepower and range of a machine gun, coupled with the precision and ergonomics of a rifle. The SIG SAUER NGSW-AR 6.8mm submission is an ultra-light, medium-caliber machine gun with AR ergonomics and is chambered in 6.8mm hybrid ammunition. Features include quick-detach magazines, side opening feed tray, increased available 1913 rail space for night vision and enablers, folding buttstock and a suppressor.

sigsauer.com

Caliber/Bore: 6.8x51mm Hybrid, 7.62×51 NATO
Barrel Length: 16in
FFL Status: N/A
Type of Links: M13 disintegrating link
Rate of Fire: N/A

ST KINETICS

STK 50

The STK 50 machine gun fires from an open bolt, eliminating “cook-off” of ammunition. It has semi- and fully automatic firing modes, selectable from a push-type selector at the trigger module. Left or right feeding allows quick change-over of ammunition type, and the quick-change barrel with fixed headspace allows the barrel to be changed within seconds without adjustment of headspace. The STK 50 is designed for easy maintenance without the need for special tools.

stengg.com

Caliber/Bore: 12.7mm
Barrel Length: 1,141mm
FFL Status: N/A
Type of Links: Disintegrating M15A2 link belt
Rate of Fire: 400–600 RPM

S&T MOTIV

K12

S&T Motiv’s K12 7.62mm machine gun is easily converted from aircraft mode to infantry mode. It uses an open-bolt operation, is belt-fed with a quick change barrel and has a gas-operated and rotating bolt locking system for greater reliability. The K12 can be mounted to a bipod, tripod or aircraft. The machine gun has multiple integrated MIL-STD-1913 mounting rails for optics, lights and laser devices and is fully automatic only.

sntmotiv.com/eng

Caliber/Bore: 7.62mmx51 NATO
Barrel Length: 22in
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 650–950 RPM

U.S. ORDNANCE

M2A2

The U.S. Ordnance M2A2 machine gun is an air-cooled, belt-fed machine gun that fires from a closed bolt and operates on the short recoil principle with fixed headspace and timing. It is capable of both sustained automatic and accurate single-shot fire. It can be mounted on a vehicle, boat, helicopter or other aircraft. Ammunition may be fed from either the left or right side of the gun, making it suitable for use by both infantry and in armored vehicles. The M2A2 weapon system has been tested to well over 50,000 rounds. Its single-breech lock system allows for field rebuild, eliminating the need for depot-level maintenance during its lifetime and thereby greatly reducing logistical support.

usord.com

Caliber/Bore: 12.7mm
Barrel Length: N/A
FFL Status: N/A
Type of Links: N/A
Rate of Fire: N/A

ZID (OPEN JOINT STOCK COMPANY “V.A.DEGTYAREV PLANT”)

Pecheneg 6P41

The 7.62mm 6P41 Pecheneg machine gun is intended to engage hostile manpower, fire means and aerial targets. The whole range of rifle cartridges is used to fire from the machine gun. The gas regulator ensures the reliable operation of machine gun automatics in various operating conditions. The high degree of commonality with the PKM machine gun and similar layout of its automatics action ensure the reliability of the Pecheneg machine gun in any operating conditions. The 6P41 Pecheneg incorporates some design novelties aimed to increase the effectiveness of barrel cooling, which has allowed a spare barrel to be eliminated from the machine gun set.

zid.ru/eng

Caliber/Bore: 7.62mm
Barrel Length: N/A
FFL Status: N/A
Type of Links: N/A
Rate of Fire: 600–800 RPM

AUSA 2014

Paul Evancoe — Fri, 03 Jul 2015 07:15:46 +0000

ABOVE: PD-100T Black Hornet PRS (Personal Reconnaissance System) is about the size of a dragonfly.

The focus of the annual AUSA (Association of the United States Army) show at the Washington, DC Convention Center is always on the newest war fighting technologies. This ranges from aircraft, armored vehicles and logistics support equipment to munitions, firearms and optics. Because of the exorbitant costs associated with research and development, along with the extensive time and resources it requires, most hardware on display is not new technology. Rather, it’s either the refinement of existing technology or the result of off-the-shelf items where adaptive engineering has created a marriage of existing technologies to provide a new capability, or more often, the illusion of something new and revolutionary.

When walking the floor, one can only cringe at all the “new” AR assault rifle variants being promoted as a better mousetrap. This author confesses to being unimpressed by much of the AR variations; it’s overwhelming and underwhelming at the same time. Most all launch the same 5.56, 6.8 or 7.62 round. They employ a variety of floating barrels, conventional barrels, conventional and mono-uppers and lowers, hundreds of different fore ends, and exotic metallurgy and composites. Their operating systems are either clones, or close variants, of Gene Stoner’s traditional AR gas operating system, or Mikhail Kalashnikov’s short stroke gas piston operating system. Their ergonomics may vary slightly, but most all are adorned with quad Picatinny rails so the “operators” can hang all their “Gucci” lights, lasers and aiming devices on the gun, making it look cool with marginal increase in combat effectiveness and increased dependence on battery power.

Largely because of the cost of R&D and an abundance of competing DoD priorities (translate that to funding), it seems there are few new small arms that reflect invention; or as PEO Soldier says, “game changing technology.” Real game changing technology is always hard to develop and it’s always expensive. That’s because pushing the limits of engineering and science is always involved. We have, therefore, turned our attention away from the AR variants in search of invention with other types of potential.

L2J1PG comes as a short AR-style pistol grip mount for the M203. (Courtesy of LMT)

FLIR Systems, Inc. really knocked it out of the ballpark this year with their new HISS-XLR rail clip-on thermal weapon sight. This sight allows target classification and engagement at ranges up to 2,000 meters (environment permitting). The XLR uses a cryogenically cooled infrared detector housed in a closed circuit cryogenic micro-cooler that has no moving parts. Unlike other cryogenically cooled infrared detectors, the XLR’s Dewar doesn’t require recharging. The advantage of a cryogenically-cooled detector is its high sensitivity and resolution over the uncooled variety. Those attributes, coupled with a high definition organic LED (OLED) display screen, provides a remarkably tighter and cleaner presentation to the user. The XLR is weatherproof and will reliably operate in all environmental extremes ranging from arctic to desert.

FLIR also showcased their first mobile phone-based consumer product. FLIR ONE is the world’s first personal thermal camera for iPhone 5 and 5S that
incorporates FLIR’s groundbreaking Lepton-Camera Core. Lepton is the smallest IR camera available today and FLIR developed it at their expense. It contains an uncooled, long wave, 80×60 pixel low-resolution sensor. FLIR ONE is about the same dimensions as the iPhone 5. The iPhone 5 simply slides into the FLIR ONE sleeve, an operating app is downloaded into the iPhone, and you’re in business with your own powerful infrared imager that operates as if it’s an integral part of your iPhone. FLIR ONE is powered by its own rechargeable battery and draws no power from the iPhone. The iPhone powers the app and itself. The thermal image is viewed on the iPhone’s screen like any other image, except FLIR ONE has 7 different colored screens that can be selected by the swipe of your finger. This selection aids in finding the best viewing color unique to a particular target and its surroundings. It also has a “thermies” capability that accurately measures the temperature of the target within +/-1 degree C up to a range of 15 feet. FLIR ONE is an affordable, user friendly, serious IR imaging capability that anyone can purchase with uses only limited by the imagination.

Prox Dynamics (PD), a Norwegian world leading Nano UAV manufacturing firm, located right outside Oslo, Norway, debuted their PD-100T Black Hornet PRS (Personal Reconnaissance System). This is the night capability version of the PD-100 that has been in operational service in Afghanistan for over two years. The PD-100T has integrated a thermal and daylight camera with fused imagery that will provide warfighters with a low or no light tactical ISR capability and it provides full night/low-light thermal real-time video and high definition snapshots that are relayed back to the base station. The complete PD-100 system consists of three parts; a base station with a seven inch view screen (although there is an option for a head-mounted monitor), a pocket transport package containing two nano-helicopters, and a multi-voltage charging and transport unit. Interestingly, the T camera carried in the PD-100T helicopter is the miniature FLIR Lepton camera described above. The self-stabilizing nano-helicopter only weighs 18 grams (less than an ounce). It has a range of about a mile with a 25 minute flight endurance between charges. It flies at a speed of about 10 knots and can negotiate wind gusts up to 20 knots with a service ceiling of 8,500 feet ASL (above sea level), though the operational altitude will normally be in the range of 10-300 feet AGL (above ground level). The helicopter can be manually directed using the control unit, or programmed to fly a given route based upon GPS waypoints. When the helicopter gets low on power it automatically sends the user a low battery message and will return to the control unit automatically (a hands off homing feature) for easy recovery. These nano-helicopters are slightly larger than a common dragonfly (insect) making them virtually invisible and inaudible beyond short distances. Like the FLIR ONE, uses for this affordable and powerful capability are only limited by the imagination.

U.S. Ordnance’s M60E6 performance rivals the M240 machine gun. (Courtesy of U.S. Ordnance)

An elegantly simple, yet inventive design manufactured by Lewis Machine and Tool Company (LMT) in Milan, Illinois, is an anodized aluminum adapter stock that allows a standard M203, 40mm grenade launcher to be mounted to it without any modification or special tools and used as a dedicated grenade launcher much like the M79. The stock comes in two variants: the L2H1PG has a full-length six position SOPMOD stock and AR-style pistol grip, and the L2J1PG comes as a short AR-style pistol grip mount, minus the shoulder stock. This means any agency with M203s can now employ them as a lightweight, rucksack or sling-carry stand-alone, without having to dedicate their ARs to the additional bulk and weight of a permanently mounted M203. Better, the M203 can be quickly removed from the Lewis stock and returned to the AR if desired. No modifications are required of the M203. Available to Federal agencies and law enforcement, this simple, low cost, interoperability solution affords them M203 new mission versatility.

A firearms attention getter this year (and exception to the AR boredom the author was experiencing) was a tactical submachine gun built by the Turkish arms manufacturer, Sarsilmaz: the SAR 109 T submachine gun chambered in 9mm NATO. Its blowback operating system fires from the closed bolt at a rate of 900-1,000 rounds per minute. Its hammer forged 6 polygonal rifled barrel has a right hand twist that offers a spin length of 1/10 inches. The upper and lower are milled from 7075 aluminum. The gun has a telescopic stock, a quad rail, and offers the same ergonomics in stock, grip and safety/fire that the familiar AR-style rifles have. Sarsilmaz offers both 20- and 30-round steel and 30-round polymer magazines, along with sturdy folding front and rear detachable sights. This deadly little sub-gun will reliably and accurately spoil your opponents’ day at ranges out to 100 yards. Put a sound suppresser on the muzzle and its special purpose mission application for close quarter battle, e.g., ship boarding, building clearance, or as an aircrew PDW, is obvious.

Those reading this who think the M60 machine gun is no longer a viable battlefield 7.62 machine gun – raise your hands. No matter what you think you should visit U.S. Ordnance and take a close look at their new M60E6. With an advertised 100,000 round life expectancy and comparable performance to the M240, the M60E6 is a refined and lethally thoughtful weapon work of art. Being a vintage Vietnam warrior myself, I cut my combat teeth with the M60. We shortened the barrels, took the butt stocks off and removed the bipod and carrying handle. These crude measures cut a bunch of weight off the otherwise truculent M60 and improved its handling in the dense jungles. The new M60E6 has it all. In addition to its 30% better feed pull, it has extended feed paws that protrude above the feed tray to prevent the linked ammo belts from falling out of the tray while the top cover is open when reloading. The carrying handle has been lightened and moved from the receiver to the Stellite-lined barrel, allowing the quick change of a hot barrel without the use of gloves. A Picatinny rail is located on the top cover and 3, 6 and 9 o’clock rails adorn the lightweight fore grip, providing plenty of space for accessory attachment. Most subtle (and brilliant), the gun’s gas piston is now reversible (it can’t be put in the wrong way). That, in itself, is worth a high five from every M60 gunner who ever carried one.

HISS-XLR rail clip-on thermal weapon sight. (Courtesy of FLIR Systems, Inc.)

Overall, the M60E6 is lighter, more compact, more ergonomic, more ambidextrous, and easier to handle than ever before. Will the U.S. military ever give up on the M240 and return to the M60 as its main 7.62 machinegun? Probably not for a variety of reasons, but that isn’t stopping other armies like the Danish Army, who have recently selected this fine machine gun as the replacement for its aging MG-3s.

Last, a discussion about General Atomics’ railgun technology is in order. Unlike a coilgun, which employs a series electromagnetic coils triggered sequentially at precise times, a railgun uses two bus bars (rails) to conduct the current lineally along the barrel (not bore) through a cross-connector (armature) that turns the current from one rail and back down the other. The force generated is analogous to that of the hydraulic force that straightens a curved fire hose. Railgun-fired projectiles ride the inside of the launch barrel in a sabot – the projectile itself is not in contact with the barrel. As the projectile exits the barrel, the sabot is stripped away from the projectile by aerodynamic lift, and the high velocity projectile is on its way to the target. A typical target can be a missile, a floating platform or something land based. Current railguns are large systems that require large power generators and capacitor storage banks. Using current technology, (Navy funded for shipboard application), a land based system would require two mammoth M1070 tractor-trailer units that each carry generators, thermal management apparatus, a battery unit and pulse power unit. These two trailers plug into a third tractor-trailer unit that carries the railgun, ammunition magazine and fire control system. This railgun system is based on shipboard installation requirements, where volume is less precious. General Atomics is working to reduce the size of land-based mobile systems, but for now, it’s big, but it’s also “bad!” The Railgun can shoot a multipurpose projectile over a hundred miles with pinpoint accuracy several times a minute. Future versions can even shoot ballistic missiles out of their in-bound trajectory prior to reentry. The railgun’s long-range projectiles have a guided capability that gives them their pinpoint accuracy and allows them to adjust their path in flight. There are even special projectiles used for space targets that contain small maneuver-thrusters for steering/course correction in a
non-air environment.

The importance of this emerging railgun technology to the future battle-space is that it provides a single weapon with a multi-role capability. Its elimination of propellant, high capacity (deep magazine), and low engagement cost, along with its minimum requirement for kinetic kill energetics, significantly reduces it logistics tail. Its precision accuracy in air and missile defense, counterbattery fire and surgical strike additionally offer a low potential for collateral damage. As this technology is perfected, we will undoubtedly see it shrink in size, but will it ever become man-portable? The scientific answer is that this technology will be refined and, at some point, it will become smaller, lighter and modular. That said, it will reach a point where the laws of physics will limit the reduction of its size and it can go no smaller. Man portability may never be attained, but robot modular portability potentially could if such a capability was seen as operationally justifiable and cost effective. More exciting however, is the likely refinement in its accuracy and capability through the use of super sophisticated fire control computers that are interoperable with other powerful target detection and direction systems. While General Atomics flatly refuses to discuss the potential (and understandably so), there is no reason why this gun couldn’t be used to shoot hostile satellites out of space orbit (with little to no attack signature). There is also probably no reason why, if fired from a sea based, or friendly country’s mobile platforms, it couldn’t be used to shoot down hostile ICBMs during the boost stage, or the orbital phase, or take out the launch facility all together. Again, the imagination is the limit for this technology.

So closes this year’s AUSA adventure, but stay tuned, there are many other exciting technologies and applications to discuss in future articles.

FLIR ONE and iPhone 5. (Courtesy of FLIR)

Torture Tests: The U.S. Ordnance M60E6

Dan Shea — Fri, 03 Jul 2015 07:15:32 +0000

SADJ has known and covered the products from U.S. Ordnance in Reno, Nevada for many years. Their US MK43 Mod 0 (M60E4) machine gun is state-of-the-art and the M2HB .50 caliber machine gun from their shops is known around the world for its quality. Over the last few years, U.S. Ordnance founder Curtis Debord, Sr. and Sales & Marketing Vice President Steve Helzer have been traveling to more and more countries with their products and, after many customer requests, decided to begin manufacturing the famous MAG 58, with U.S. M240 features incorporated. Wanting an outside observer, U.S. Ordnance asked SADJ to cover a full military specification style testing regimen. After we finished the full M240 testing, we started talking about the upcoming M60E6 machine gun.

Since the Danish Army has now fully adopted the M60E6, we decided it was time to bring this innovative and well thought out machine gun to our readers. Matt Babb and I showed up with our woolies and repeated our foray into the cold Reno winter air and put the hammer down on two versions of U.S. Ordnance’s M60E6… and were pleasantly surprised.

The M60 General Purpose Machine Gun (the “Pig” in ‘Nam talk) was born in the post-World War II era and was actually inspired by the German MG42 machine gun, among other designs. The U.S. government was looking for a replacement for both the M1918A2 BAR and the M1919A4 LMG. Both weapons were very reliable and had served well in training and combat for 30 years. Both the Ordnance Board and Aberdeen Proving Ground had noted the advantages of some of the lighter weight weapons made by the Germans; notably the MG42 and FG42 machine guns, and began experimenting. Students of historical firearms will of course recognize the operating system of the Lewis machine gun as well. The first forebears of the M60 were somewhat odd designs in .30-06 caliber, and by 1951 the M60 GPMG was born as the T161. (Many of the tests, designs, and photos of these early M60s are archived online at www.smallarmsreview.com). Interestingly, there are a small number of these T161 machine guns registered in the civilian community in the U.S. It wasn’t until 1957 that the M60 was adopted into service by the U.S. Army, in caliber 7.62x51mm, as the Squad Automatic Weapon that paralleled the M14 rifle in caliber. Now, the service had maintained a battle rifle and machine gun in the same caliber.

This author has had the pleasure of meeting and interviewing some of the designers of the M60 back in the 1980s, and gained some insight into the thought process and requirement that the designers went through. One engineer explained that the M60 was designed as a modular system in which parts could be easily replaced and the receiver had a life that was specified to be 100,000 rounds. All military firearms have life cycles that are assigned to them, and these are expected replacement points. For example, the M249 receiver has a stated life of 50,000 rounds, and the M240 receiver is 60,000 rounds. The technical specifications on the M60 called for a 60,000 round life, but the designers had targeted 100,000 rounds. There are cases where the robust yet heavier M240 machine guns are known to have fired in excess of 2 million rounds without receiver repair, and the M60 had a receiver stretch gage issued to armorers. During the Vietnam War, U.S. troops gradually integrated the M60 into the fighting units but one tactic evolved that the designers had never foreseen: door gun use on helicopters as daily duty. It was not unusual for an M60 to be used on daily missions where the treelines around perimeters would be pounded for 5-6,000 rounds in a day before landing in an LZ. Clearly, many of these M60s would be facing terminal life at a month’s use, but they soldiered on. Quite a few of these worn out guns were donated to Central American fighters in the 1980s, and this has led to legends about how “Bad” the M60 was. The fact is, the M60 GPMG was a very reliable machine gun, and while it had its problems, it was quite popular and faithful to the machine gunner who kept it clean and properly lubed. Speaking as someone with long experience with the M60, this author can state without hesitation that the M60 was much easier to field. The rounded edges and lighter weight than its predecessor M1919A6, or the M240 that succeeded it, made it far more comfortable to carry, and it was simpler to work on in the field and operate under fire than the M1919A6. Of course, the M1918A2 was an Automatic Rifleman’s weapon in a squad, limited to 20-round magazines, so even though the M60 was to replace it as well as the M1919A6, it truly was used in a different role.

In the 1980s, Saco Defense (manufacturers of the M60 included Springfield Armory and the variations of Maremont Corporation, ending with General Dynamics) was involved in some JSSAP upgrade programs, and the “E3” was born. A lot of reliability changes were made, but one change that was global in effect on the system was moving the bipod from the barrel to the receiver group. It was a nightmare to try to change the barrel on the “Pig” under fire, keeping a low profile, because the weapon had to be supported and moved off of the bipod and a new barrel installed. This is why most operators report that they never changed a barrel in a firefight (although, to be honest, very few operators on a small unit level will EVER change a barrel in a firefight; it’s lost time and not something you think about in the heat of battle). With the advent of the M60E3, this changed. Another important modification was that in the E3 top cover, the feed cam was changed so that the cover could be closed with the bolt forward and then charged. With the old M60, the bolt had to be to the rear in order to close the top cover. Third, the E3 added a two notch operating rod; the second notch was intended to stop the “runaway gun” syndrome with underpowered ammo or when the M60 got very dirty inside.

The E3 was accepted, and upgrade programs began, yet by the 1990s the M240G and M240B were adopted and put into service, with a smaller caliber M249 “SAW” adopted as a belt fed automatic rifle at squad level in the U.S. Army and USMC. The M60E4 was the new competing generation, but it experienced a higher rate of rounds between failures than the M240, thus the services were willing to take the higher weight and length of the M240 series over the M60. (Note that this M60E4 was NOT the same as the M60E4 that is made by U.S. Ordnance today; U.S. Ordnance has a much better design and reliability record on theirs). The M60E4 was adopted in the 1990s by NAVSPECWAR for the Navy SEALS as the MK43 Mod 0, and with its shorter barrel and overall size and weight, has served reliably for over 20 years.

There are literally tens of thousands of M60 GPMG and M60E3 machine guns in service worldwide today. These modular weapon systems are getting tired, and the countries that have them in service are generally looking at replacement programs.

This has driven the duality of our Mil-Spec test design. With the adoption of the M60E6 by the Danish Army, a major Western military has now moved to the newest evolution, so SADJ decided that not only was it time to get this full testing done, but to add the upgraded M60 to the test and run it in parallel. The market for the M60E6 is not just new buyers, it’s complete upgrades to existing inventories in many countries.

As noted, U.S. Ordnance, the subject of this article, has been a military contractor for several decades, and supplies the U.S. M60E4 and U.S. MK43 Mod 0 machine guns, as well as the U.S. M2HB .50 caliber machine gun and a new quick-change barrel M2A2 variant. (We’ll be testing this soon as well). In their new plant in Reno, Nevada, they have the capabilities to manufacture almost any modern weapon system, and the MAG 58/M240 series was a project they recently dove into. That decision was made for them by the many requests from their customers around the world and since the demand was there they would apply their skills to the program and join the market. It was decided not to compete in the U.S. military market as FN Manufacturing and Colt have the longer term contracts; whereas the immediate needs of their foreign customers were an excellent starting point. However, U.S. Ordnance is the manufacturer of the M60 series machine guns and the current counterpart for the U.S. military, so it made economic sense to them to present the E6 upgrade to the U.S. military as well.

U.S. Ordnance has many strong points in their manufacturing capabilities, and they used them all through the production process. The modern U.S. Ordnance plant in Reno, Nevada has almost any capability from R&D to CNC, to “Cutting Chips,” to barrel making, and one of their strongest points is in their heat treating capabilities. They’ve been able to extend the life of many of their parts because of the deep study and knowledge they’ve put into this subject. For example, their operating rod on the M60E4 and E6 programs has a unique longevity for that part due to this knowledge base, and U.S. Ordnance’s induction heat treatment all the way through these parts has had the effect of reducing this wear point significantly. To be honest, it was this particular part that several of us kept checking – all us old M60 guys. That tower on the op rod just gets hammered, and the ones from U.S. Ordnance’s M60E6 program showed no wear at the end of the test. Very impressive, indeed.

M60E6 on the left; M60 to be upgraded on the right. Center is the M60E6 upgrade kit we would use.

This author has been involved with numerous tests over the years, so it was quickly decided to consult with several military and industry testing professionals to work up a regimen that answered the following questions:

1- Is the M60E6 up to Mil-Spec?

2- Will it perform through a U.S. Mil-Spec test?

3- Are the parts interchangeable for full function testing?

4- What are the Mean Rounds Between Failures compared to the old tests?

5- What is the barrel life and how is the dispersion testing?

6- What is the interchangeability with other M60 variants in existing national inventories? Can they be reliably upgraded to E6?

The tests were designed to answer these questions in a proficient and comprehensive manner. We invite our readers to understand that while this type of test sounds like fun, it is in fact a grueling and demanding task with many hours and many people working to keep the details in order to not invalidate the terms of the test. Since we know that U.S. Ordnance’s 100,000 square foot facility is ISO 9001:2008 certified, and are familiar with the production facility, we just went right to getting answers to the questions about the new M60E6.

One of the best ways to check on a production line’s quality control is to switch out the parts on different units and test them. Interchangeability is critical in a machine gun and it was decided to do this test indoors at the U.S. Ordnance facility instead of on the range. Several weapons were disassembled and interchanged, and function testing was fine. This is what was expected from a combat production weapon – that the parts will interchange and function without fitting or modification. U.S. Ordnance has over 15 years of experience as a company and the management/engineering team has experience going back to the 1970s; so this was no surprise and indicated to customers that they can have confidence in these weapons regarding the supply chain. Parts to U.S. Ordnance guns will work in any of their production weapons. This author has seen parts for machine guns made all over the world, and recommends that the end user gain his supply of spares from the Original Equipment Manufacturer, especially an OEM like U.S. Ordnance with very high quality control.

US Ord’s ingenius barrel cooling system consisted of a pipe with nozzles to direct air from a field compressor into the barrels. This really helped speed up the testing time, and didn’t cause the problems encountered with water baths.

Perhaps more important to our test, was taking an original Maremont M60 GPMG and stripping it to the receiver, gaging it, and rebuilding it with modern U.S. Ordnance M60E6 parts.

The point of our test was to hammer down on a production E6, and an original “Pig” upgraded to the M60E6 form, and to do this in parallel at the range: Nose to nose, so to speak.

In addition to testing of 100 rounds per minute at intervals and 200 rounds per minute in sustained fire, there is a new test called “Hasty Defense.” This new protocol that USMC and Big Army are planning to implement is 1 minute firing at the cyclic rate of the weapon. In the case of the M60E6, that would be a 650-round continuous burst. Since we were using lightweight barrels, an adjustment had to be made for safety’s sake. We moved Hasty Defense to a 400 round sustained burst.

We chose to fire the Hasty Defense test as part of the main test at the very end of the test. Because of their work with the M60 series machine guns and M2HB machine guns, U.S. Ordnance has Stellite lining capability in-house and the E6 barrels were Stellite lined. Thus, before the final accuracy testing, we chose to “put the hammer down” and end with 400-round bursts. We’re trying to beat on these weapons in a methodical, repeatable test, and find out what they can handle.

Army TM9-1005-224-10, the Operator’s Manual for the M60 GPMG, calls for the following rates of fire:

Sustained: 100 RDS/M (4-5 seconds between burst) – Change barrel every 10 minutes.

Rapid: 200 RDS/M (2-3 seconds between burst) – Change barrel every 2 minutes.

What this Operator Manual describes is not a Mil-Spec “Test,” it’s simply the recommendation for the user for his barrel change times. Additionally, there is the “Hasty Defense” test previously mentioned. We chose to intersperse the Sustained and Rapid rates of fire throughout the tests, to achieve a more homogenous result on both weapons and simulate the changing rates of fire found in real use.

The Main Test:

25,000 rounds through each of two U.S. Ordnance M60E6s

The real benchmark to reach for is reliability. In U.S. government test wording: The machine gun shall demonstrate a Mean Round Between Stoppage (MRBS) of 7,500 rounds and a Mean Round Between Failure (MRBF) of 25,000 rounds over a minimum receiver service life of 50,000 rounds. Barrel life shall be 15,000 rounds minimum. This is a pretty aggressive protocol. As an example, while the U.S. Government specifies this, the results of the 1994 competition between the Saco Defense M60E4 and the FN M240 were more realistic: the M60 had 846 Mean Rounds Between Stoppages and 1,669 Mean Rounds Between Failures, while the M240 (which was adopted) had 2,962 Mean Rounds Between Stoppages and 6,442 Mean Rounds Between Failures. Neither weapon achieved this mythical MRBS or MRBF number.

While the M240 appeared about three times as reliable in these early tests, it’s important to remember that these weapons had very different end uses in mind and the M60E4 was a much lighter and smaller weapon and the E4 variant was not fully evolved. The U.S. Ordnance M60E6 was a much better contender in our tests, as the reader will note below.

In order to properly do the testing, a series of firings at set intervals were to be done with the two M60E6 machine guns; one off the combat production line from U.S. Ordnance, the other an upgraded Maremont M60. These machine guns would have to undergo the grueling test until they each reached 25,000 rounds, and the testers would have to rigidly observe firing, cleaning, and parts replacement requirements from the test protocol. Grueling on the testers as well…

Once the testing started, the protocol had to be observed. Barrel temperature had to be kept within certain ranges, and burst firing had to be kept to the details of the test. We found that the barrels needed to be cooled to about 100 degrees F in order to stay within our barrel change guidelines. Each M60E6 was supplied with three barrels and U.S. Ordnance had designed an air
cooling system for forcing air through the barrels to shorten the process between firings. None of the testers like the idea of cooling barrels in water during a test like this.

The test protocol was the same as used by the U.S. military with some modifications due to the weather:

We used Mil-Spec 7.62x51mm NATO M80 ball ammunition linked 4 ball to one tracer (M62), in 200-round belts. This ammunition was Malaysian manufacture in the 1970s and both U.S. Ordnance and this author have used this ammunition extensively and found it to be extremely reliable. Due to recent lack of ammunition from the main U.S. manufacturers and the long delivery times, we opted to use this ammunition. Unfortunately, this ammunition is reaching the end of its life cycle and a number of ammunition related failures were experienced. (Primer and powder have definite lives defined by their chemistry; depending on how it’s stored relates to longevity). Since these failures to extract or fire, and some double feeds were readily identifiable as ammunition related, they do not count towards MRBS and MRBS. As a test matter to prove that theory, at the 12,000 round point, we switched to 2000s manufacture Lake City ammunition for 1,000 rounds and experienced no problems (but did note an increased cyclic rate).

Accuracy testing was performed at rounds 1, 10,000, 20,000, and 25,000. The first tests had a 5.5 inch spread on 8 rounds at 100 meters range. By the end of the testing, one set of barrels showed a 6.5 inch spread, the other set was 8 inches. A very acceptable performance and we were all pleased with this result and did not consider this a serious degradation.

Many U.S. Ordnance employees are retired or former military. It is a company policy to draw as many veterans into their workforce as possible. This not only works towards their company culture, it is a big “thank you” from U.S. Ordnance to the veterans, and it ensures that the people building the weapons know a lot about those weapons. Jerry Pierson, Retired USMC Infantry Gunnery Sergeant at U.S. Ordnance, and a retired USMC Infantryman, described the production protocol that U.S. Ordnance goes through before shipping machine guns: “In production, accuracy on all raw barrels is checked from a fixture fired 10 rounds, then the barrels go to finish. Then, each barrel is tested on the actual gun for function, 50 rounds per barrel. Then, the gun is tested with 10 lb. belt pull firing 5 rounds simulating lifting a 200 round standard ammo can’s worth. In each shipment of 100-300 guns, one is randomly selected and removed for 1,000 round full test and inspection.” That should explain the quality checks that are being done, and reassure the customer on that issue.

View from the barrel accuracy testing. After 25,000 rounds, none of the barrels had “Spread” the beaten zone for more than about 2 inches at 100 meters. Outstanding performance!

On to the Live Fire

Our firing rates were defined as follows:

200 rounds “slow” was a 7 round burst, then wait 10 seconds and repeat up to 200 rounds then change barrels and move to “Fast.”

200 rounds “Fast” was a 7 round burst, then wait 3 seconds and repeat up to 200 rounds, then change barrels and move to “Slow” again.

We marked the barrels M for the upgraded Maremont gun, O was for the new U.S. Ordnance made gun. This allowed us to keep the test parts with the proper M60E6s.

At 2,500 rounds, each gun was broken down for a quick field strip and general inspection, light cleaning and lube.

At 5,000 rounds, 10,000 rounds, 15,000 rounds, and 20,000 rounds, a full cleaning was done with inspection and minor parts replacement scheduled if needed.

At 10,000 rounds and 20,000 rounds, certain parts were scheduled to be replaced and this was done. These parts were: ejector, extractor, and the firing pin and recoil springs. This is protocol, and we adhered to it as all testers do.

The U.S. Ordnance manufactured M60E6 experienced a few ammunition related problems; and one instance of an extractor that was replaced with a field extractor which had a problem (not a new extractor). At 20,100 rounds, part of a case broke off and blocked the bolt. Still, that’s an ammunition issue but we called this a Stoppage. In all, we had two stoppages in the U.S. Ordnance manufactured firearm, and no failures.

The Maremont upgraded M60E6 had some problems with the ammunition, until a lubrication schedule was instituted and extractor replaced. At 16,000 rounds, there was a small parts breakage on the right rear tower on the operating rod: the firearm kept running, but the part was replaced at this point. The only real stoppage attributable to the weapon was at 23,801 rounds; the extractor broke and was quickly replaced.

Mean Rounds Between Stoppages (MRBS) is determined by dividing the total number of rounds fired by the total number of stoppages. “A stoppage is defined as any unplanned cessation in firing or the inability to commence or cease firing attributable to the gun. All incidents shall be recorded and any considered as not chargeable to the machine gun shall be substantiated by the contractor.” During testing on the U.S. Ordnance manufactured M60E6, we had 6 total stoppages that were properly attributed to the ammunition. Ammunition issues (failure of ammunition) do not count in this type of test. We had one stoppage attributable to a part failure. The math on that is: 25,000/2=12,500. That’s 12,500 Mean Rounds Between Stoppages. For the upgraded Maremont gun, we had 14 total stoppages that were properly attributed to the ammunition. We had two stoppages attributable to a part failure. The math on that is: 25,000/3=8,334. That’s 8,334 Mean Rounds Between Stoppages.

Result? The U.S. Ordnance manufactured M60E6 system outperformed the U.S. specification of 7,500 Mean Rounds Between Stoppages by a factor of 1.5. The Maremont M60 upgraded to the M60E6 system outperformed the U.S. specification of 7,500 Mean Rounds Between Stoppages by a factor of 1.12. That’s outstanding and beats the old test data from 1994.

Mean Rounds Between Failures (MRBF). MRBF is determined by dividing the total number of rounds fired by the total number of failures. “A failure is defined as any stoppage which involves part replacement or requires in excess of one minute to correct; or involves any failed or damaged part detected during scheduled preventive maintenance, the replacement of which is not authorized at the crew or organizational level of maintenance as prescribed by Source Maintenance Recoverability Code and TM-9-1005-313-23P.” The MRBF numbers are the same as for Stoppages, since we only experienced ammunition
related problems.

We’ve already mentioned the capabilities that U.S. Ordnance has at their facility. It’s necessary when supplying military grade firearms to stick to a specification for manufacturing process. However, there will be certain procedures that can be changed to produce a more durable product, as long as the R&D and production teams know what the issues involved downstream are.

U.S. Ordnance wanted to ensure full compatibility with all mounts and accessories, so the M60E6 will mount onto all M60, M60E3, M60E4 mounts, and will accept the M60D spade grip configuration, although if “D-grips” are the plan, it’s best to order M60D to begin with.

U.S. ORDNANCE, INC.

300 Sydney Drive

McCarran, NV 89434

United States of America

www.usord.com

Tel: 775.343.1320

Fax: 775.343.1331

Sales: sales@usord.com

Marketing: marketing@usord.com

Support: support@usord.com

Training: training@usord.com

Photos by Shay Swetech

FFECREATIVE.COM

www.smallarmsreview.com

The U.S. Ordnance M2HB .50 BMG Machine Gun

SADJ Staff — Thu, 18 Aug 2011 23:31:17 +0000

U.S. Ordnance M2HB shown with a U.S. Ordnance Mk93 cradle, Vinghøg AS Vingfoot Combi Lightweight Tripod, B.E. Meyers Flash Suppressor, and US Ordnance improved sighting system. (U.S. Ordnance)

The United States Government (TACOM) has just announced an order has been placed with U.S. Ordnance, for 548 M2HB Flex .50 caliber machine guns. SADJ is pleased to bring the story of US Ordnance’s “Ma Deuce” to our readers as the US Government is gearing up its inventory.

U.S. Ordnance is a woman owned manufacturing defense contractor located in McCarran, Nevada, just outside of Reno. U.S. Ordnance is rated as a small business, and they are “cutting chips” daily and manufacturing is in-house. Among their other products such as the M60E4/MK43 machine guns, they manufacture their M2HB .50 caliber machine guns in their new 68,000 sq. ft. manufacturing facility. With newly purchased state-of-the-art equipment and an indoor firing range, U.S. Ordnance has the ability to accurately and efficiently produce and test their products to the industry’s highest standards and the company is ISO 9001:2000 certified by DNV. Using the latest manufacturing techniques, U.S. Government monitoring and responsible sales ethics, they deliver reliable and comprehensive products and services to their customers.

U.S. Ordnance manufactures and provides firearms that are extensively tested, safe, and battlefield proven effective. In April 2000, U.S. Ordnance was licensed by Saco Defense (now General Dynamics Armament and Technical Products, Inc.) to manufacture the complete line of M60 machine guns. The initial licensing agreement transferred the contractor owned technical data, processes and procedures, contractor owned tooling, gages and fixtures to U.S. Ordnance. In February 2006, the balance of the required Government owned production tooling used on the M60 machine gun was transferred from Saco Defense to U.S. Ordnance. Since then, U.S. Ordnance has manufactured thousands of complete M60 machine guns (models M60E4, M60E3, and M60D) for the U. S. Government and other commercial and foreign contracts. Starting in early 2007, they started developing their M2HB machine gun.

Standard U.S. Ordnance M2HB shown with M3 tripod. (US Ordnance)

All U.S. Ordnance products are developed and tested to NATO specifications and made to the original technical data package. A critical consideration for the company was maintaining those original specifications. U.S. Ordnance customers benefit from extensive environmental endurance testing, such as drop tests, ice, mud and water immersion, to deliver the most reliable firearms. Each U.S. Ordnance machine gun produced undergoes proof firing, as well as function and accuracy testing before it leaves the factory. This 100% testing ensures quality control. Due to the success of their firearms worldwide and current production for the U.S. Government, U.S. Ordnance can assure availability of replacement parts in the future. In addition to their M2HB and M60 line they offer the M16/M4 variants, M203 grenade launcher, and M40A3 sniper system.

M2HB Background
The M2HB .50 caliber (12.7x99mm) is an air-cooled, belt-fed, machine gun that fires from a closed bolt, operated on John Browning’s venerable short recoil principle. This weapon system first went into design in the early 1920s, and was in full use by the mid-1930s. Affectionately called “Ma Deuce,” it fought through World War II, Korea, Vietnam, countless wars and conflicts around the world including Iraq and Afghanistan today. The current iteration of the M2HB is capable of both sustained automatic and accurate single shot fire. The M2HB machine gun is used extensively as a vehicle, boat, helicopter or aircraft mounted weapon by the United States and most NATO countries. Ammunition may be fed from either the left or the right side of the gun making it suitable for use by both infantry and in armored vehicles. The M2HB is in service with the U.S. Military and the armed forces of over 23 nations and is the world standard in heavy machine guns.

U.S. Ordnance flaming Bomb logo and 1NZN0 acage code on a newly manufactured M2HB machine gun receiver. (U.S. Ordnance)

Key Features of the U.S. Ordnance M2HB

Parts interchangeable with M2HB machine guns produced in the United States,
Can be fitted to all types of armored, light and heavy vehicles, patrol boats, helicopters and aircraft,
Fires all types of ammunition: Ball, Tracer, AP, API, APIT, AP and Multipurpose rounds,
Left or right hand ammunition feed and cocking,
Can be fired manually or by solenoid.

Available Options and Improvements

Improved quick adjustment sighting system with Integrated M1913 Picatinny rails for mounting optics and laser aiming devices,
Optional positive safety selector for the trigger mechanism to prevent accidental discharges when they are traveling over rough terrain while manning the weapon system,
Optional flash reducer/suppressor,
M2QCB – Quick Change Barrel option also available.

U.S. Ordnance understands the importance of ensuring interchangeability for mature weapons systems such as the M2HB. They have already successfully demonstrated full interchangeability for the M60 weapons system with those produced by Maremont Corporation and Saco Defense. Their ISO established processes, procedures, quality assurance controls, production testing, and methods of manufacture ensures the level of quality required for all components of the M2HB machine gun are also maintained.

Newly manufactured U.S. Ordnance M2HB receiver components just prior to riveting. (U.S. Ordnance)

Production Capabilities
In 2007, Norman Justice (see sidebar) and U.S. Ordnance senior management agreed to fund development of a U.S. Ordnance M2HB weapon system. The initial stage involved designing and building the necessary tooling and fixtures required to assemble the various components and design and ordering of the tooling to produce the required castings and forgings. This process required four full-time tool and die makers to develop and build tooling and production fixture and inventories of $2.5 million worth of weapons grade material, castings, and forgings were ordered. In 2007, the economy was booming, metal prices were at an all time high, and weapons grade metal castings and forgings took 28 weeks from order to delivery.

In October of 2008, U.S. Ordnance took occupancy of its company owned, 68,000 square foot facility in the Tahoe-Reno Industrial Center. This custom building included expanded capabilities, such as an automated Phosphate Coating System, and an indoor live fire test range that can handle full auto .50 caliber Standard Ball Cartridge and .50 caliber High Pressure Test Cartridges, and a high security customs bonded warehouse.

This building expansion occurred at just the right time because over $5 million worth of new equipment dedicated to their M2HB production was starting to arrive. Their prior facility did not have sufficient floor space for this larger equipment and they had exhausted their available electrical supply. This new equipment under Norman Justice’s guidance and prior experience was grouped into cells and dedicated to their M2HB and/or M2HB subcomponent production. In layman’s terms this translates into very accurate volume production. In most cases these cells run 20 hour shifts, five days per week.

In September 2008, U.S. Ordnance received a contract from TACOM-RI for 859 Non-standard M2HB for Afghanistan. This contract had an aggressive delivery schedule with the first delivery occurring just 60 days later in November. While actual monthly production figures are confidential SADJ was able to confirm that U.S. Ordnance delivery schedule of 100 per month is current. In addition to this they have supplied several foreign allies with undisclosed quantities of M2HB weapon systems on DSP-5 export license as part of their direct commercial sales program.

Downrange view thru the U.S. Ordnance improved weapons sight. (U.S. Ordnance)

Process and Product Improvements
As part of their continuous effort to improve the M2HB weapon system, U.S. Ordnance has perfected the fabrication process associated with the barrel extension to mitigate cracking of this critical component. Cracking of the barrel extension is a common problem with the M2HB after prolonged use. Within the last year, an improved barrel extension was provided to Special Tactical Services and used in the course of their training programs. Over 120,000 rounds were fired with no degradation of the barrel extension. The changes made reflect modifications to the manufacturing process while the resultant design completely conforms to the M2HB TDP

Another product improvement developed by U.S. Ordnance is their improved sighting system. With its simplicity of use, the user can concentrate on the target allowing for rapid target acquisition. The large heads-up ballistic compensation knob can quickly be changed without losing eye contact with the target, and can be accomplished even while wearing gloves. An integrated Mil-Std 1913 Picatinny rail allows for mounting optics, IR or visible lasers. The front and rear sight fold out of the way for a clear sight picture when using optics or aiming devices. Any U.S. made M2HB can be retrofitted with the U.S. Ordnance improved sighting system.

Small Arms Readiness Evaluation Team with Repair (SARET-R)
U.S. Ordnance offers their customers a Small Arms Readiness Evaluation Team with Repair (SARET-R) program. U.S. Ordnance technical experts supplement existing customer SARETs by assisting in the inspection and maintenance of their small arms. As a manufacturer, U.S. Ordnance can supply just-in-time components necessary to maintain and repair their customer weapons systems. “Ensuring proper function and safety of our customer’s military equipment is an essential part of our service offering,” said Daniel Fassler, Director of Operations. “We have assisted our customers in developing SARET-R programs around the world and have helped to dramatically increase their overall weapons readiness.”

U.S. Ordnance has achieved large-firm M2HB manufacturing capability while maintaining the small-firm customer focus that has made their M60 program so successful.