Well I read about this AR45 on www.cncguns.com and this guy makes a lower that accepts the old "grease gun" magazines(45acp) that are still quite available and hold 30rds. I got really interested in them until I got on the forum he has,and saw how long it has taken some of the guys to get these lowers,and they aren't cheap either. He doesn't finish the lowers himself,sells them as paperweights,and has a FFL licensed machinist finish them if you don't have someone that can do it. I really like what he has done because I have never cared for the setup that Olympic uses with their lowers. It is just hard to cough up over $400 for a completely machined lower/stripped,and then still have to deal with an Olympic 45acp upper.