Does this barrel extension look like an M4 one?

I

Ioncannon

Regular
Rating - 100%
3   0   0
Got my new barrel for the AR I am building but I am not sure if it has M4 feed ramps. Do these look right?

4g1Ftx9.jpg


icAT9Ju.jpg


olWiHTF.jpg


I saw other pictures and rifle extensions do not seem to have cutouts from the side. So I assume it is a M4 extension? (Sorry for blurry pics)

gcnDnRa.jpg
gcnDnRa.jpg
 
Last edited:
Phew, thanks guys. I saw some pics recently where the ramps look way more flush and got worried. I guess it depends on the manufacturer?
 
It's hard to tell without comparing them side by side, but from the pics, that does not look like M4 feed ramps on your extension.

They vary from manufacturer to manufacturer, but they should be flush. I have a DD/Sabre here and they fit flush and a Wilson/RRA and they fit flush both with M4 feed ramps. M4's also fit flush.

I am a Colt and Colt Canada certified armourer BTW.
 
C77 said:
It's hard to tell without comparing them side by side, but from the pics, that does not look like M4 feed ramps on your extension.

They vary from manufacturer to manufacturer, but they should be flush. I have a DD/Sabre here and they fit flush and a Wilson/RRA and they fit flush both with M4 feed ramps. M4's also fit flush.

I am a Colt and Colt Canada certified armourer BTW.
Click to expand...

M4 feed ramps are not flush with the edge of the barrel extension. They are cut back into the extension in such a way that from the bottom it looks like two notches in the extension.
 
I am in agreement with C77 on this - I can also attest to his background. They almost look like 1/2 way regular/M4 feedramps. Easiest thing to do is assemble it and run it...you will figure out PDQ if it'll work.

Boltgun
 
Well… M16 feed ramps are not cut back in to the side of the barrel extension… clearly yours are… but they should be flush with the receiver, or at least recessed… you appear to have a lip when the barrel is in the receiver. Having a lip that the tip of the cartridge can catch on is the “bad” situation.

But, what really stands out to me is that the slots where the bolt lugs lock into are rounded. They are typically squared off. This would suggest to me that the barrel extension is not to spec… and thus the feed ramps are probably not to spec.

Where is the barrel from?
 
Mirk said:
Well… M16 feed ramps are not cut back in to the side of the barrel extension… clearly yours are… but they should be flush with the receiver, or at least recessed… you appear to have a lip when the barrel is in the receiver. Having a lip that the tip of the cartridge can catch on is the “bad” situation.

But, what really stands out to me is that the slots where the bolt lugs lock into are rounded. They are typically squared off. This would suggest to me that the barrel extension is not to spec… and thus the feed ramps are probably not to spec.

Where is the barrel from?
Click to expand...

Green Mountain from here. I just took it to the gunsmith cause I needed it drilled out for the front sight block, and he confirmed they weren't M4 feed ramps (or not to spec). He said he'll cut them to spec with no charge, so at least there is a silver lining. Still, kinda #### that the barrel was cut poorly.

I wrote in the "special instructions" of Wanstalls' order form to cancel the order if it did not have M4 feed ramps (they say it's a MILSPEC extension). So either they don't read that form or they also thought they were M4 feed ramps and it was just poor manufacturing.
 
You must log in or register to reply here.
Back
Top Bottom