Lightweight, compact rifles are highly sought after in the United States military. However, the supply of these weapons is often constrained by budget or other issues. The USMC, especially, does not have the budget to replace all of its M16A4s with M4s, as the Army seems to be doing – and apparently the Army is moving towards replacing all of its M4s with M4A1s, or at least as far as the barrels are concerned.
Furthermore, the USMC doesn’t want to completely abandon the extra velocity offered by the M16A4, and is apparently looking forward to future conflicts as well. “Every Marine a Rifleman” is probably not far back in the equation, as well.
Therefore, what the Marine Corps could do is make its current rifles more maneuverable and adaptable to different situations, different Marines, and different amounts of gear worn by said Marines. I’m speaking, of course, about a collapsible stock. However, the solution is not as easy as attaching a carbine lower to a rifle upper. While many who shoot brand new semi automatic rifles will never know of the potential issues, on full auto – or with a well used rifle on semi – MRBS (mean rounds between stoppages) drops to merely 30. This is reportedly a result of bolt bounce.
Bolt bounce occurs when the bolt, propelled forward by the action spring, makes contact with the barrel extension at high speed. As metal objects are prone to do when they come in contact with one another at high speed, they “bounce” apart. In this case, the bolt partially unlocks. With either the M4 or the M16A4, this is where the buffer comes in. The weight inside the buffer slams forward a moment after the bolt has gone into battery, preventing it from bouncing back by adding just the right amount of force to the equation.
The 3 ounce carbine buffer and carbine spring, however, are insufficient for the rifle gas system, which is normally used in conjunction with a 5.2 ounce buffer and a longer spring. One could, as the Canadians have done with their version of the M16 series rifle, simply use a heavier buffer, which would eliminate some of these issues. However, this means reduced compatibility with other weapons as well as a wide variance in carrier velocities and other consistency-related issues.
Enter Vltor Weapons Systems, manufacturer of a variety of firearms and accessories, from the upcoming Bren Ten to popular stocks like the EMod and receivers such as the MUR and VIS. Vltor developed a 7 position buffer tube that is slightly longer than the standard carbine tube, attached the excellent EMod stock to it, and also developed three buffers – up to 7 ounces – and a non-carbine spring for the system. Not only does it work with the M16A4, but it functions with the M4 and systems in between as well – in fact, Vltor says it works with all direct impingement AR-15s. The heavier buffers are recommended by Vltor for over-gassed carbines or piston systems.
This may be the ideal solution for both the USMC and civilian shooters that want to ensure that they have the best buffer system available for their AR-15s. I’m definitely looking forward to getting my hands on a system and testing it against the regular A2 stock in a rifle configuration, and other buffer systems such as the Spike’s ST-T2 in the carbine format.