I put the GRS in a 300BLK AR

I know this is a Sub dedicated to the 9mm AR but I figured I should at least share my findings with the GRS in a 300BLK AR.

For context, when I first got into firearms I bought a PSA 300blk upper years ago and the thing is very over gassed, even when running subs unsuppressed. The thing kicks like a mule with supers, very uncomfortable to shoot after like 8 rounds.

Which lead me to ask the question if the GRS can tame 9mm, why not over gassed 300blk? I put the system on my ar15 and popped out one of the 2 steel spacer weights as it was too long and wouldn't fully cycle the bolt. I just got back from testing and holy crap this thing shoots even softer than my fully tuned 5.56 AR, running an adjustable gas block and h2 buffer. This system may even have some use in rifles.

Ran the standard GRS minus 1 weight. RB5015HD, 1 Kynshot Spacer Weight, JRC Buffer Tube and a Flatwire Carbine Spring.