02/27/2026
Throwback Thursday! -When Jeff Zimba published this image of a melted M4 gas tube in 2007, he already knew the solution was gas-piston operation. Reel it back a couple of years to the 2005 SHOT Show in Las Vegas and four companies were pitching new gas-piston systems for the black rifle.
1. HK introduced their “HK M4” which was later rebranded to “HK 416”.
2. POF introduced Frank DeSomma’s “P-416” piston upper.
3. Leitner-Wise introduced their LW gas piston kit which required modification to the host rifle.
4. ARES Defense (FightLite) introduced Geoffrey Herring’s “CR-4” (Carbine Reliability M4) gas piston kit, which evolved into the “GSR-35 Black Lightning” (Gas System Retrofit, AR15 + M16 + M4 = 35) and which was then rebranded as our “GXR” Gas Piston Retrifit Kit.
Where the ARES GXR Piston system departed from the other AR piston offerings is that it was a true retrofit kit that did not require any permanent modification to the host carbine. In fact, a unit armorer could swap out an M4 direct gas system and retrofit it to gas-piston operation in less than 5 minutes! The GXR increased carbine reliability in adverse conditions, permitted much more aggressive firing schedules with a much greater heat threshold over DI gas systems, significantly reduced receiver and BCG fouling especially when used in conjunction with suppressors, and returned M4 cycle rates to a more manageable RPM by overriding eroded gas ports with an internal gas regulating or***ce.
In 2007, ARES Defense briefly licensed the GXR patent rights to Bushmaster Fi****ms whom had just been acquired by Cerberus Capital Management. One of the requisites imposed by Cerberus/Bushmaster was a 6,000 round endurance test of the GXR which was jointly carried out in Maine by Bushmaster armorer Ben Glass and ARES CEO Geoffrey Herring. A couple of the images here are from that event.
As pioneers of gas-piston systems for the AR15/M16/M4, we know without reservation that hard use carbines and machine guns benefit from gas-piston systems which is why we implement outside venting piston systems in all of our “hard use” products.
Images by .usa
