1/ Same carrier, special bolt 2/ Don't bother w/5.56 mags, get some CProducts 5.45 mags from 44 mag sales (around $15.00 each) 3/ Great uppers, I have a 20" 4/ My 20" 5.45x39 1 in 8 shoots the same as my 20" 5.56 w/1 in 9 twist 5/ Don't worry about the gas tube, if it ever goes bad - just change it out! 6/ laquer don't seem to bother the AKs in full auto, should'nt bother the AR
