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12/28/2008 3:08:44 PM EDT
Hello all! Long time lurker 1st post.I have a colt 6721 lower marked .223 and a 1997 colt upper marked "colt .223" with an m4 notched barrel that is marked c mp 5.56 1/7 on the barrel. The upper reciever has no m4 notches in it but the barrel has an m4. Should i have the reciver cut? Can i use 5.56 ammo in this weapon. Thanks for the responses
12/28/2008 3:11:23 PM EDT
[#1]
No need to make M4 cuts in the upper receiver, it'll work fine. And yes it will shoot 5.56 whatever the receiver says. Most ARs are designed to shoot 5.56
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