Gunsmithing m1a stovepipe with scope mount

[flagmanahead]

I seem to be continually getting a stovepipe when my round ejects because of my scope mount. I'm using a Brookfield mount and GA Arms 168 grain match ammo so my assumption is that mount and ammo quality are not an issue.

What else could I tweak to make this more reliable?

 

[Michael]

Re: m1a stovepipe with scope mount

Checked the gas system to be certain it's not carboned up?
A bolt open tilt test will tell.

Another possibility is a worn extractor and/or ejector spring.

 

[flagmanahead]

Re: m1a stovepipe with scope mount

Thanks, will check these first

 

[M855]

Re: m1a stovepipe with scope mount

The Ga arms so called match that ive shot was garbage it was seated at 2.70 and didnt group well ymmv,try some different ammo,I have the sadlak mount on a standard M1a with no problems,Ga arms is plinking/blasting ammo but its far from match just my 02 cents

 

[flagmanahead]

Re: m1a stovepipe with scope mount

Good to know. I have done the tilt test and I hear the click every time on the gas system so I'm sure it's not fouled.

I'm curious how to tell if the extractor is worn? Maybe someone can post a picture of a "good" one?

 

[81Z4ME]

Re: m1a stovepipe with scope mount

You can change ammo or work on the ejector. That doesn't mean there's anything "wrong" with your ejector either. I've read about some folks changing the angle on it just a little to get the empties to "fly" a different patch when it flips them out of the bolt.

Different ammo "ejects" different. My scoped M1A doesn't "like" South African surplus. I get those same jams you're talking about. The empty hits the scope mount and bounces down in the way of the bolt/next round as they are moving forward. Everything else I've shot (several types of US surplus 7.62X51 as well as my reloads) don't cause any problems.

 

[usmcMT]

Re: m1a stovepipe with scope mount

^^^^^+ 1. My AR10(When I still owned it)would not run with SA 7.62.

 

[flagmanahead]

Re: m1a stovepipe with scope mount

Is it worth trying a USGI extractor and ejector spring? I don't know the source of all of the parts but I guess if there is a way to determine if mine are USGI I could disassemble and check. Is there a way? I think it's only a $20 gamble to replace them and gives me a backup if it's not the issue....

 

[M25BeastShooter]

Re: m1a stovepipe with scope mount

I assume your Brookfield mount is original. We put Sadlak mounts on M-14's being sent to Iraq. During the course of firing we discovered that some of the rifles would jam by getting the ejected cartridge caught between the mount and the bolt. It didn't happen to all the rifles but Mike Sadlak took our recommendation and cut a 3 degree reverse bevel under the mount to allow more clearance for the shell to clear.

What I'm saying is it might not anything "wrong" with any part of the system but rather the sum of all the parts.

If you can't fix the problem by changing the ejectors, extractor, or associated springs you might try a SADLAK mount.

 

[biggame10683]

Re: m1a stovepipe with scope mount

If its a SA they will do it for free if you call them.

 

[flagmanahead]

Re: m1a stovepipe with scope mount

It's definitely a Brookfield but that is exactly what happens, the cartridge gets pinched between the mount and the bolt. Do you know where I can get original USGI parts? Fulton Armory maybe?

 

[Lumpy Grits]

Re: m1a stovepipe with scope mount

How does your rig run with out the scope and stuff on it?
FWIW: Think about a Wolff Gunsprings recoil spring and the recoil buffer.
Try diff. ammo.
Respectfully,
LG

 

[flagmanahead]

Re: m1a stovepipe with scope mount

OK I just took a much closer look at operation and at operating "speed" things run well but when I move the operating rod manually it seems to drag on something at about the halfway point. My first guess is the guide that is between the gas piston and the receiver group. Does anyone else's seem to drag about half way back?

 

[Lumpy Grits]

Re: m1a stovepipe with scope mount

What you a feeling is the bolt riding over the hammer.
Who built your rifle?
LG

 

[flagmanahead]

Re: m1a stovepipe with scope mount

This is an old rifle out of the Benning armory...4 digit serial #

Match barrel was put on it a few years ago and I "inherited" it as is.

 

[biggame10683]

Re: m1a stovepipe with scope mount

You could always send it out to someone to make it run like butter and tell them the prob you are having 2 birds one stone effect?

 

[flagmanahead]

Re: m1a stovepipe with scope mount

Just to follow up on this I replaced the ejector and extractor and it works very well now even with crappy old ammo. The spring was about 2/3 the length of the new one so i'm sure that had something to do with it.

thx for all the help!