i have a barrel and upper that does not have m4 feed ramps is that something that can be done with a dremel or pencil grinder? if so anyone know of a write up?

Bigbore (ADCO) says you can do it yourself with a Dremel Tool

You can dremel M4 feed ramps into the upper receiver if you already have a barrel with M4 feed ramps. If you have a barrel with regular feed ramps then just leave it and the upper receiver alone, should be plenty reliable.

This... All of it

If your receiver has M4 feed ramps but your barrel does not, yes!

1)  Go to ACE Hardware.  Get the Chainsaw Sharpening Dremel Kit.

2)  Go home.  Remove the barrel from the upper receiver if attached.

3)  Insert barrel into receiver.  Observe how it looks.  Imagine in your head how it should look.

4)  Remove barrel.  Dremel feedramps of barrel with Chainsaw Sharpening Kit as necessary.

5)  Repeat as necessary.


Notes:  As you work, consider the following adages from smarter people than yourself:

1)  Tools can fuck shit up.  Power tools can fuck shit up quicker.  Easy does it.

2)  You can always remove material.  Putting material back is a pain in the dick.


It's not hard, but does take a bit of finesse.  Dremel and put it back in the upper.  Dremel and put it back in the upper.  Repeat.

And for your final bit of advice:

It's not fucked up if the rounds still feed.  

If both do not have m4 feedramps, you are good. Shoot it and see the flawless performance.

As stated: leave them ALONE...ramps not necessary.

And dremel through the anodizing?  You're both out of your crack-smoking minds...

If it feeds fine as is, leave it.  No need to fix what isn't broken.

The reason the M4 feed ramps came into being IIRC was that the shortened carbine gas tube length led to an increase in cyclic rate in FA. The bolt was out running the magazines ability to push the rounds up fast enough to reliably feed/function. In SA fire it generally isn't an issue unless you are running a too light buffer/cut semi-bolt, weak action spring, marginal magazine springs or your weapon is over gassed (hobby gun with a nonspec  gas port dia. to run weak non .mil spec ammo that is running .mil spec ammo).

although magazines with a weak spring that wouldnt feed in a regular upper might feed in an upper with M4 ramps   ...but i wouldnt grind them in through the anodizing..just swap uppers..

i dont know why everybody just doesnt move to M4 ramps...

That's just the official reason.  They really just wanted to keep the clock running on the patents/copyrights/IP...