Hey how's it going ?
1) if it is stamped 223 on the barrel I would only use 223 ammo .
2) yes but you could contact DPMS and ask if you can fire 5.56 out of there heavy bull barrels
3) I would also Recommend changing out the FCG . The problem is most likely the diconect or the hammer . A FCG is about $40
4) CLP all the way baby
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If Jesus had a gun , he'd probably still be alive !
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