I just realized that my 20 inch A2 complete upper (which I bought at a gun show… I know, I know) has a m4 barrel extension with a rifle upper. Is this acceptable? Can a 20 inch rifle even benefit from m4 feed ramps? Should I remove the barrel and install a rifle extension? Any help would be appreciated.
Just to clarify… Exactly which part has M4 feedramps and doesnt have them?
I ask because if you have a standard barrel and an M4 Upper receiver, you will have 2 little holes where rounds could potentially get stuck in. In which case, I recommend changing your upper to match your barrel.
If it were the other way around though, (Barrel with M4 feedramps and a standard upper receiver) you’d be ok.
Here’s a link to a past thread on this topic.
https://www.m4carbine.net/showthread.php?t=193