Pistons are just something else to sell something to fix a problem that does not exist
For clarity the short stroke piston M4 (HK416)
was developed for a reason. That being reliability and service life from the military issued CQBR (10.5 inch M4) suppressed and with extremely heavy firing cycles was less then ideal. You have to understand that in 2003-2004 the issued 10.5in upper for certain military users was not the 10.5 inch guns we have now. We didn't have the buffers, springs, adjustable gas blocks, and fully developed barrels that are available. I have been issued and used the original CQBR, HK416, and current issued MK18 10.5 inch guns. The 416
was the piston guns all other were measured against. And truthfully was the gun
all SBR's were judged against for military use. For several reasons that is not necessarily the case anymore.
Unless you need a suppressed, short barrel rifle, for
heavy firing cycles, most users would be better served with the standard DI AR15/M4.
