Quick AR question!

[Smeh]

Will a barrel with M4 feed ramps work fine on an upper that doesn't have the M4 relief cuts?

I keep reading on different forums that it will, but many manufacturers say on their websites "Because this barrel has M4 feed ramps, it must be used on an upper which has M4 relief cuts".

Seems to me like it should work regardless, but I figured I might as well check here.

 

[Nugilum]

It will be OK. Not ideal, but OK.

Here's what it'll look like, courtesy of AR15Barrels.com:


You'll be in the "OK" pictured. The picture illustrates why a standard barrel in a M4 upper will not work.

 

[Smeh]

What problems might I run into using M4 feed ramps on a standard upper?

 

[kwelz]

What problems might I run into using M4 feed ramps on a standard upper?

None really. The problem is using an upper with the cuts with a barrel without them.