Sirex
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Exactly what I would expect from BCA. A buddy of mine bought four uppers from them a while back, two in 7.62x39 two in 300BLK... the 300BLK just flat out wouldn't work. Sent back numerous times, all came back with issues, wouldn't cycle, gas block coming loose, etc. Ended up sending back for refunds. The 7.62 uppers, it was 50/50... one ran great, no problems. The other started to have cycling issues after second magazine. Sent it back, got another dud. Sent it back, finally got one that will shoot.
With wasted ammo, times going to post office back and forth yada yada I would stay away from anything BCA.
To their credit, I have a BCA 7.62x39 upper that has run ok so far. I figured a 22 couldn't be too much worse could it? I was wrong.