The 40mm Day/Night/Thermal Program

By Jay Bell


Sometimes what appears to be a good idea is not as good as it seems. That appears to be the case in the 40mm training ammunition world. The U.S. Army’s 40mm Day/Night/Thermal (DNT) effort has stalled and then restarted on the high velocity (M918E1) and on low velocity (M781E1) but has not successfully completed the First Article Acceptance Test (FAAT or FAT). These rounds were supposed to be a major leap in technology. They achieved several key requirements of the U.S. government. The Army got rid of a troublesome fuze in high velocity and added night training capability in low velocity in order to train like soldiers fight, at night. The magic material that made all this happen is called “pyrophoric iron.” Pyrophoric iron spontaneously combusts when exposed to air. It turns out that the pyrophoric iron may not be all it was cracked up to be. It has some serious downsides: It causes range fires, and allegedly, at least one round has gone off prematurely, flashing at 3,000 degrees with the gunner inches away.

Going Back

Now, the U.S. Army appears to be going back to decades-old technology to address the training requirements for the 40mm MK19 machine gun and M320/M203 weapons. The training ammunition for these platforms goes back to the later 1960s. The Army recently made an award to go back to the M918:M385 2:1 Mixed Belt configuration in December 2019. There was also a “Sources Sought” notice that came out in November 2019 to re-ramp for the projectiles, which were shelved a few years ago. The main producer had an auction in July 2019, since the DNT rounds appeared to be the path forward.

The Sources Sought announcement officially kicks off the procurement process for a 5-year “Indefinite Delivery Indefinite Quantity” contract to buy these 1960s technology, high-velocity projectiles. The high-velocity and low-velocity images are the old school rounds—a cutaway of the M918 Flash Band smoke and the M781. These images are courtesy of the U.S. government, and the comments are from one of the early Industry meetings highlighting the deficiencies circa 2014. Images of the M918E1 and M781E1 show only the outside of the new rounds. The insides are not available for public consumption. I attempted to get pictures from the Army, however, due to all the issues with the 40mm E1s, they were not letting any more pictures out. However, all of the market intelligence seems to point back to the 2004 Ted Haeselich patent, with chemical glow stick material in the middle of the round contained in a glass ampule (numbered 21/22). This ampule breaks and mixes upon setback to give a “lava” spurt downrange at night upon impact. The #13 item would be the standard orange powder or “signal dye.” This is to signal the impact area of the round.

Original U.S. government program timeline for the DNT program (see 2013).


A Little History

Since the 1990s, the 40mm high-velocity training ammunition option has been less than desired by the U.S. military. The 40mm M918 “flash, bang and smoke” round had multiple issues:

1) It had an expensive fuze that did not always function as desired and especially had problems in soft range conditions—sand, mud, wet, etc.

2) The fuzes did not have a self-destruct feature.

3) Projectiles that did not function are “unexploded ordnance” UXO and could cause injury if kicked or picked up.

4) The M918 was known to cause range fires that would shut down the training activities in some environments.

5) The M918 had a higher hazard storage and transportation class for the round.

The USMC became so fed up with the M918 situation that in the 1990s it stopped buying the Army’s M918 and started buying the MK281 from a small German company called NICO. The MOD 0 version had an orange signal dye like the Army’s low-velocity M781. Ted Haeselich worked at NICO in the 1990s and into the early 2000s. After an extensive adventure to fully type-classify the round, costing hundreds of thousands of dollars, the USMC made large purchases of the MK281. Later when NICO was purchased by German Military giant Rheinmetall, Rheinmetall started a U.S. manufacturing facility, and the orders skyrocketed. The original contracts to Germany were around $30M, and once they had the U.S. final assembly included, the contracts shot up to the $300M range. The story is a legend in the defense community.

Ted Haeselich’s patent with chemical glow stick material in the middle of the round contained in a glass ampule (numbered 21/22).

The MK281

The MK281 was perfectly simple. Basically, it is a high-velocity M781. It had a proprietary propulsion design that threads the projectile to the cartridge. The round must shear metal to fire, which is much more consistent than crimps and adhesives. The results are greater accuracy downrange. Later versions of the round added chemical luminescence aka glow sticks, to give a nighttime impact signature. It did not have a fuze, so there was ZERO chance of a dud. An additional plus is that the chemical luminescence materials are totally safe, ala Halloween glow sticks for kids. It can be eaten by kids on Halloween, and they can still eat all the candy they can handle. To meet the requirement of the DNT, the chemical properties were adjusted to add more heat to the process to be picked up with thermal imaging. The chemicals can be tweaked for colors, brightness, duration of glow and heat output.

The German cartridge design is favored by a lot of military forces around the world. Due to some old conflict over patents, the desire for 100% American-made products and a few other reasons, the MK281 has never seen full acceptance in the U.S. It does have one drawback, the chemical luminescence glows a rather long time. When you are training at night and shoot a large number of rounds, say 50 to 100, the target area will end up glowing so much that it is hard to tell when the last round hit. This phenomenon was coined as washout.

The Army Plan

The U.S. Army’s Project Manager Maneuver Ammunition Systems (PM MAS) started the planning for this next wave of development a long time ago. The 40mm DNT Industry Days date back to the early 2010s. The U.S. Army’s competition to solve its need for an improved M918 would be the M918E1 and in low-velocity M781E1. The M918/M781E1s had several key requirements:

1) No or minimal range fires (M918 only);

2) No fuze to fail and reduce costs (M918 only); and

3) Day, Night and Thermal visibility and/or signal (both rounds–new for M781).

PM MAS would have companies compete for the prize of making the rounds. The winning design would get the initial multi-year development contract and be in the leading position to make the rounds for the next 50 years. The M430 effects are the visual effects from an M430A1 HEDP round at 500m. The Army wanted a similar nighttime effect as seen in night vision.

On to the Competition

Nine companies submitted bid samples for evaluation in both 40mm high-velocity and low-velocity versions. These companies spent millions of combined dollars to get their designs mature enough to withstand the rigors of DOD testing. This field included American Ordnance (AO), Amtec, Chemring Ordnance, Cyalume Technologies, General Dynamics (GD), Rheinmetall, ST Kinetics (Singapore) and Universal Defense. Some did not even make it to the testing phase; some failed out early in testing.

These nine were down-selected to two competitors for high velocity—Amtec and AO Ordnance—and two for low velocity—Amtec and GD. Would the 40mm powerhouse Amtec, continue to dominate the 40mm world? Or would the large businesses with their success in ordnance in AO and general small/medium caliber ammunition expertise allow GD a win? Ultimately, it was AO as the high-velocity winner and GD as the low-velocity winner. The MK281 was in the mix along with several other varieties; however, it did not make the cut.

The competition had several deciding elements. The most important was pyrophoric or chemical luminescence. The best attributes of pyrophoric material were: a high heat output for thermal, bright visual light/explosion for the naked eye and lower hazard for storage and shipping. The best attributes of chemical luminescence were that it was totally inert and had zero risks of range fires. The negatives for pyrophoric was the “potential” for range fires. The downside of the chemical material was that it is difficult to see at 1,200m with the naked eye and the washout effect, as described above. The winning solution ended up being a pyrophoric solution for both rounds, which appears to be a key reason the programs have had so much difficulty.

Magic Material

Pyrophoric materials are processed iron particles that are contained in a glass ampule without air. When the ampule breaks and is exposed to air, it oxidizes quickly—actually, very quickly, which results in a lot of heat and a lot of light. It is technically a flash of light; some people might mistake it for a small explosion. The waste material is iron powder. It can be thrown away without concern about hazardous waste. It’s pretty awesome. The more interesting attribute is that if you break the top of an ampule off, the material will just simmer. You would just notice a color change and a slow process happening. If you turn the ampule over, you get a sparkler light show all the way down to the ground. If you smash it against the ground at 700m per second, you are back to the explosion-like effect.

The downside of pyrophoric material and what caused the program to be placed under a temporary Stop Work order is that the rounds were causing a lot of range fires—there was a safety incidence where the round in the chamber was broken and flashed in the weapon (potentially injuring the gunner)—and other performance issues. The M918E1 has a plastic ogive, and underneath it are some pretty powerful materials. The MK281 also has a plastic ogive; however, if this round breaks in the cycling of the MK19 machine gun, the glow stick material is not going to harm anyone.

Low-Velocity Status

The M781E1 delay issues are a little less well known. GD has not made it through first article testing, where AO is in production and has been awarded option quantities already. Is it the same pyrophoric range fire issues as M918E1, or is it something else? The drop test for pyrophoric could be to blame. The standard M781 could never pass a NATO standard 1M drop test. By the look of the design, I imagine that it would still be a problem. The pyrophoric material would make things interesting if it broke upon impact.

I have always been critical of the U.S. government’s typically painstakingly slow methods and processes. They test, test again and then test some more. Then repeat all those tests in multiple temperature phases. Once you are sure you have it nailed, they have someone else try to repeat the results exactly. It can be quite maddening at times, and you wonder how anything gets done. The 40mm DNT program seemed to be moving at light speed. It was extremely impressive. This current situation has given me a greater appreciation for taking it slow. The U.S. government goes slow when one item has been changed. In this case a little more so.

Pyrophoric materials have been successfully used in other military areas like aircraft countermeasure flares. However, it is still a newer process. The processes and applicant for 40mm had to be developed and built for these programs. Sometimes plans don’t work out at well as one would have hoped. This may be the case with pyrophoric—that it is just a little ahead of its time. There are a lot of people in the industry that think the M918E1 and M781E1 are doomed to failure. They believe the range fires might result in the M918E1 and M781E1 to be shelved, and we will go back to the 1960s designs, at least for a little while, and then either back to chemical luminescence or a newer material.

M918E1 the high-velocity round reducing the UXO hazard for the U.S. government.

The government’s original timeline from a 2013 Industry Day shows the program transitioning to full-rate production over / around 5 years. In reality, it took about 6 years. If they have to go back and re-invent the wheel, it will take another 5 years. These things just take time. This is one case where too new and not enough testing set things back, maybe a decade. Only time will tell.