The 9×39 Cartridge
There is a paucity of real, hands-on information available on the 9x39mm ammunition. What we did find states that there are two different variants of the 9x39mm ammunition. One, the SP-5, is conventional ball ammunition. We only had available less than ten rounds of this, so we did not disassemble it. The other is the SP-6 round, which is a black tipped armor piercing ammunition.
We spent the better part of the only delightfully sunny day of our visit on the range performing function, velocity, sound, and crude penetration testing. The temperature was 83.5/29 (F/C), humidity was 37%, and the station pressure was 675 mmHg. The velocity of sound calculated to 1,143 ft/sec. We used the protocol in Mil-Std-1474D with the microphone 1 meter to the left of the muzzle 90 degrees to the bore axis and 1.6 meters above dirt (there was no grass in sight). For sound measurements, we used the Larson-Davis 800B with the LD 2530 1/4 inch pressure microphone and a recently re-certified LD CA250 calibrator. For velocity and rate-of-fire measurements, we used a PACT chronograph/timer.
For our non-suppressed sound levels, we shot the SP-6 ammunition in the Vikhr. The non-suppressed average was 159.8 dB with a zero standard deviation. Velocity was 957.5 ft/second for the SP-5 SNIPER and 961.4 ft/second for the SP-6 armor piercing. Rate of fire was 789 rounds per minute.
Suppressed, using the VSS, the measured sound levels were: 130.0, 130.3, 130.8, 129.0, 127.5, and 130.8 decibels. This averaged to 129.7 dB for a respectable reduction of 30.1 dB. The first round was 0.3dB louder than the average of the remaining rounds, and the standard deviation was 1.17. Velocity averaged 924.3 ft/second; only slightly less than the velocity in the Vikhr. With the SP-5 Sniper AP ammunition, the cyclic rate of the VSS rifle was 960 rounds per minute. This increase compared to the similarly designed Vikhr is predictable due to increased bore pressure of the suppressed weapon causing more rapid opening of the action.
We did measure the sound level and velocity of a few rounds of the standard SP-5 ball ammunition. The velocity measured 905 ft/second and the sound level was 120.8 dB for slightly less than 39 dB reduction. The decreased velocity and sound level are probably due to a heavier bullet containing a lead core rather than the steel core of the SP-5 Sniper ammunition.
The 9x39mm cartridge is indeed a formidable piece of small arms ordnance. Although we only weighed the AP projectile, its weight of 245 grains, velocity of 924 ft/second and kinetic energy at the muzzle of 470 ft-lbs makes this a definitely lethal weapon. The VSS was pleasant enough to shoot. The trigger pull was among the better military triggers, and the recoil was not unpleasant.
“I wouldn’t hesitate to consider the VSS or the AS-VAL for an operation in areas that contact is likely to be under 400 meters, and consider that forces who may encounter this weapon should train up on it. After reasonably extensive testing, I have a new respect for this weapon design, and look forward to testing more modern variants. Contrary to claims I had seen repeatedly written that the VSS couldn’t stand up to fully automatic fire, my opinion is that it certainly could, at least long enough to perform more than a few live fire missions. In that case the VSS is an excellent choice as a close-in marksman’s rifle with serious AP capability that can double as an effective SMG for close encounters.”
“Although the suppressor system is an older, rudimentary design similar to other Russian offerings, that does not make it ineffective on the battlefield. This system is purpose designed to be a formidable weapons system. While we do not know which came first, the ammunition or the weapon, I suspect that they were designed as a package. The ammunition is definitely specialized to accomplish a specific task, and the weapon is designed to maximize the capability of the ammunition. As a 200-300 meter silent sniper system, it is hard to beat having a highly effective lethal subsonic projectile, outstanding penetration, reliable cycling, and fully automatic capability for when circumstances really go down the tube.”