AR Sponsor
Posted: 2/28/2007 9:20:33 PM EDT
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Newbie question and I tried search but no luck. What is the difference between a reg upper and an M4 upper? Is it the feed ramp cut only? Must you use and M4 barrel with and M4 upper...what combination of barrel to upper parts work? I am considering the M4 CMT upper for my first build. Thx. SDlocal |
AR Sponsor