The SU-15: Serbu Firearms' new upper for the AR-15/M-16!
February 9th, 2015 by Serbu Firearms
Serbu Firearms' new upper receiver for the AR-15 platform uses a different operating system which eliminates the need for a buffer and buffer tube! The operating rod houses the main spring, and the gas system uses a fixed piston. The result is a gun that runs much cleaner, is more reliable, and can be more compact than any AR-15 which uses a buffer tube... [read more]