Gunsmithing Milling .100" off of feed ramp to accommodate OAL?

[High Binder]

Hey guys, I installed new DBM and the AICS mags will hold all of my different loads but I get about .100" worth of interference with my longest load in the mag. I would really like to keep my loads what they are as they are wicked good loads and this issue prevents me from utilizing the full length of my mags. Anyhow, what are your thoughts as to milling off .100" of the feed ramp to accommodate the longer OAL bullets in the AICS mags?

 

[Just Jim]

Re: Milling .100" off of feed ramp to accommodate OAL?

No need to mill away the entire feed ramp. AICS are center feed, so you need only cut a shallow notch.

Cheers... JIm

 

[wnroscoe]

Re: Milling .100" off of feed ramp to accommodate OAL?

Use a .250" diameter center cut end mill and make a plunge cut in the center of the feed ramps leading edge. The cut will be a .125" radius notch. Look at a 591 Surgeon for reference, same/same. This will allow you to use a modified AI magazine with a longer COAL round.

 

[300sniper]

Re: Milling .100" off of feed ramp to accommodate OAL?

i think some pretty respectable people in the industry recommended against it. that said, i have done it to several without any problems.

all you need to do is plunge straight down with a 1/4" endmill, .100" into the base of the ramp.

 

[High Binder]

Re: Milling .100" off of feed ramp to accommodate OAL?

Did you guys radius the cut on the feed-ramp side at all?

Thanks or the info guys!!

 

[Hellbender]

Re: Milling .100" off of feed ramp to accommodate OAL?

A carefully applied chainsaw file works just as well if you don't have a mill (or even if you do).

 

[mcfred]

Re: Milling .100" off of feed ramp to accommodate

I know at least one of the bottom metal manufacturers makes a bottom metal that moves the magazine back slightly so you don't have to cut the front of the receiver and weaken the support for the bolt lug. This seems to be a common issue, so I don't get why the common solution is to hack the receiver?

 

[GasLight]

Re: Milling .100" off of feed ramp to accommodate

I think the ones that move the bottom metal back (Seekins? IIRC) requires you to cut the rear of the magazine well where the screw hole is for the front screw of an ADL trigger guard. There is only so much room there, with the notch like pictured here, you can run the mags and bottom metal that are already very common...

Dave

 

[300sniper]

Re: Milling .100" off of feed ramp to accommodate

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: McFred</div><div class="ubbcode-body">I know at least one of the bottom metal manufacturers makes a bottom metal that moves the magazine back slightly so you don't have to cut the front of the receiver and weaken the support for the bolt lug. This seems to be a common issue, so I don't get why the common solution is to hack the receiver? </div></div>

you still need to "hack" the receiver to use the bottom metal you are referring to. only instead of a easy 5 minute job on the mill, or at home with a chainsaw file, now you actually need to do real machine work. with the bm you are referring to the bolt needs to travel further to the rear, meaning your bolt stop will need to be modified and/or relocated.

the common solution is common because it is quick, easy, cheep/free and uses common magazines and bottom metal.

 

[mcfred]

Re: Milling .100" off of feed ramp to accommodate

Right, when you move the magazine back then the rear of the receiver needs to be notched. The rear of the receiver does not need to hold 50,000+ psi.