RCM

RCM HK53K (5.56/.223) Barrel - Threaded 15x1 RH US made 922r compliant HK53K barrel.  Specifications: Made In The USA Threaded 15x1 RH Counts As 1 US Made 922r Compliant Part Cold Hammer Forged...

RCM HK G3/91 36 Degree Locking Piece #17   One of the best ways to slow down & tame that HK21. Can also be used for HK91/G3 special projects such as suppressors, & heavier than normal...

RCM HK G3/91 (7.62x51/.308) Barrel - Threaded 15x1 RH Made by RCM to the highest tolerances and finest material available. Perfect for that HK build or to replace that shot-out barrel. Each barrel...

RCM HK G3/91 Threaded Barrel - 5/8x24-CHE Machined by RCM from a Mil-Spec 41V50 Hammer Forged Blank. These blanks are considered to be one of the finest made. 1:10 twist, Nitride finish. Perfect for...

RCM Trunnion For The HK91/G3 Series - US Made This part is machined from ordnance grade 9310 enhanced steel and heat treated to exact HK specifications. This item is the best USA-made trunnion on the...

RCM HK93 Trunnion Made to exact factory HK specifications for the HK93, HK33  type builds. These are the best trunnions of their kind on the market. Machined to HK spec making the install...

Complete Bolt Group - RCM - HK Style MP5K 9mm Ideal to replace out of spec, worn or broken bolt groups or for that custom build. Each bolt group will work and fit on semi or full auto MP5K 9mm style...

RCM Rollers, + & - Sizes RCM US-made locking rollers are available in both plus and minus sizes, making them the ideal choice for adjusting bolt gaps. These rollers are the top-tier locking...