It's been a few months since this thread was started. Since that time I can definately tell you that there is night and day differance as far as accuracy goes between a upper reciever made from alumium vs the polymer....I've not given up on the 15-22, but it is now simply a nice lightweight plinker for the grandsons.....I bought a Sig Sauer 522, heavy barrel, metal upper, and it is far far superior as far as accuracy goes...The Sig just suits my expectations much better...........best regards Plum