Sorry I'm a little late to this party, but I work at a machine shop that supplies parts for rock river arms. We are shipping out the first batch of carbine length tri rails for these for anodizing on monday, should be about another two weeks before we finish the first batch of pistol length ones. We went out to the range with some of the rock river guys a few weeks ago and they had ten pds's out there being shot, including a carbine length one that I was told had 25,000+ rounds through it that had yet to be cleaned or lubed (besides the initial lubing after assembly). I didn't see any of them