M14 Forum

Coltfan · February 2nd, 2012, 04:13 PM

I hope to get some insight from the more experienced M14'ers here. I have a SAI M1A with SAI bolt. I installed a Sadlak mount and changed out the factory extractor for a GI from RA Parts. I'm still getting a 5% failure rate with stovepipes even though I changed to a GI extractor. The cases are obviously hitting the underside of the mount which is retarding the throw of the empties. Is there another angle I can pursue to improve ejection and gain better clearance of the mount ? I appreciate any help advice. Thanks !

EBRbuilder · February 2nd, 2012, 06:12 PM

Make sure that the nuts on your scope rings are on the left side... Less for the casing to hit.

RHallenbeck · February 2nd, 2012, 06:16 PM

Did you change the ejector out to USGI as well??

Rick

RAMMAC · February 2nd, 2012, 06:26 PM

What kind of ammo are you using?
What kind of scope?
Are you getting a lot of brass marks on the bottom of the scope mount? I'm talking about the area just above the top of the magazine.
Are you aware of the what a the tilt test is and have you conducted it?

Coltfan · February 3rd, 2012, 06:50 AM

Scope ring cantilevers are on the left side. No interference from them.

I haven't changed the ejector out. Still SA.

Using 1980's Hirtenberger milsurp. ammo.

The scope is a Nikon ProStaff 4-12x40 MilDot with Warne medium QD cantilevered rings.

I am getting brass marks on the underside of the mount. It ejected perfectly and with authority before installing the mount. Zero stovepipes before installation.

I havn't heard of the "tilt test" and have not done it yet.

ericbale · February 3rd, 2012, 07:52 AM

I had the exact same problem.

I tried a nunch of fixes, cleaning, lubing, different ammo, different scopes, two different extractors, polished the chamber, unitized G/C.

Solved it by installing a sadlack spring guide and Tin gas piston.

Don't ask me why it fixed it, but I think I had a timing issue caused by binding of the action.

I still had periodic brass strikes on the mount, which I didn't like.

Later, I installed a basset mount and it sits higher and the entire problem went away for good.

Young guns · February 3rd, 2012, 08:06 AM

I had this same proplem when i mounted a Sadlak on my M1A it would hit the back portion of the mount and get stuck. I fixed it by getting a diferent mount, i went with an ARMS 18 split rail since there is no rail in the center of the mount. Or you could get a SA Inc. #4 steel mount which is similar to the Sadlak but has a cut out in the center of it.

Coltfan · February 3rd, 2012, 08:32 AM

Those are all good considerations so far. I've researched the "tilt test" and will do that today. I think I'm going to concentrate my efforts of the gas system with a swap for a GI ejector too.

I'm ordering a gas shim set (rings) and will take a serious look at gas port alignment when I do this. I'll make sure the gas tube and piston are free of any carbon and rough areas. In addition, I'll look at a deburr and polish of the factory spring guide. I want to make certain I have optimal, consistent gas pressure to run the bolt before I start tweaking other things and swapping out a bunch of parts. Once I make sure these things are optimal I'll recheck for any needs then.

You guys have prompted some thoughts here. Keep the ideas coming. Thanks.

Chief Sapulpa · February 3rd, 2012, 08:41 AM

My aluminum Sadlak mount caused the same stovepiping with Hornady TAP and Lapua Mega ammo; 110 grain and 150 grain ammo. Mine passed the tilt test with this ammo. I solved the problem by de-scoping the rifle.

awmp88 · February 3rd, 2012, 09:20 AM

Now you have me wondering if I should get a Sadlak mount , which was soon to be my next purchase on my Springfield M1A Scout.