Two PlumCrazy lowers on .22 AR uppers here with no problems. Perfect for the .22 uppers. Did shoot some with a 7.62x39 upper using 154gr soft point which gives that platform approx twice the recoil as a 5.56 upper...again no problems. Yes their take down pins if pulled hard can come all the way out and then you lose the nipple that goes on the spring. Did that with one of mine when I was swapping lowers all the time. Replacement came within a week.
I had 3 new uppers coming of which 2 were the CMMG .22 uppers. I did not want to spend $229 for a complete lower for the .22s and was not interested in building three new lowers for the uppers. So I opted for two Plumcrazys' after talking to a guy who had one on his Delton 223 upper and over 5000 rounds fired the last couple of years with no problem. I put a standard Aluminum lower on the 7.62x39 simply because the rifle points and balances better for me in that config.
However now that the PCs are both mounted on the .22s that is where they will stay. My wife is weight sensitive and the Plumcrazy lowers were very pleasing for her handling the weapon. I would not want to use them for bashing down a door with my butt-stock but neither would I with my aluminum lower based weapons either.
I had 3 new uppers coming of which 2 were the CMMG .22 uppers. I did not want to spend $229 for a complete lower for the .22s and was not interested in building three new lowers for the uppers. So I opted for two Plumcrazys' after talking to a guy who had one on his Delton 223 upper and over 5000 rounds fired the last couple of years with no problem. I put a standard Aluminum lower on the 7.62x39 simply because the rifle points and balances better for me in that config.
However now that the PCs are both mounted on the .22s that is where they will stay. My wife is weight sensitive and the Plumcrazy lowers were very pleasing for her handling the weapon. I would not want to use them for bashing down a door with my butt-stock but neither would I with my aluminum lower based weapons either.