M1A Barrel Timing issue (gunsmith reccomendations)

[Psudeonym]

I've been tinkering with my M1A (late production springfield armory, purchased used, none of the serial numbers match) trying to find some accuracy, and i noticed that the op rod was hitting the piston waay off to the side, like 3-4 mm.

I tried nudging the op rod guide with a hammer, but i guess when this one was produced they really wanted to keep the op rod guides in place, i can see knurling or something cut in to the bolster that the op rod guide is pressed on, and the roll pin keeping it is really substantial, and really deep in to the barrel material.

I figured that if they went through so much trouble to keep the op rod guide in place, they must have set it's angle pretty carefully, so i checked the angle of the feed ramps, and they are off from center about 7 degrees counterclockwise.

in a way this makes sense, because my windage always had to be set way over to the right.

I've compensated my zero but i was wondering if the barrel being out of time by around 7 degrees would cause mechanical issues aside from messing with barrel harmonics and leading to increased op rod and piston wear.

I don't know any gunsmiths in the bay area, and i'm wary the tools i'd have to buy and the risk of messing up headspace if i tried to do it myself. So if it's just the issues i've mentioned i think i'm fine with that for now. Otherwise if there would be big trouble from this i guess i'd like to know if anyone knows a gunsmith near the bay area who works on m1as.

[jarhead714]

You need an armorer, not a gunsmith. I think there’s one in Oregon. Maybe check the M14 Forum. Some barrels will not time to certain receivers I believe.

[GunDog]

I'd recommend contacting Springfield Armory, Inc. first to discuss the issue with them.

The M14 guy in Oregon is Ted Brown of the Shooters' Den. Ted is is located in the Medford/Jacksonville area and is a very knowledgeable and skilled craftsman for U. S. military service rifles.

http://www.tedbrownrifles.com/

[Dirk Tungsten]

OP, you said none of your serial numbers match. Do you have an early gun with all USGI parts?

[smoothy8500]

OP, you said none of your serial numbers match.

There's only one serial number on M1A/M14's and Garands, the other numbers are drawing numbers. They could be GI or Springfield Inc.

Nevertheless, it probably should go to Springfield to get the timing or op-rod guide straightened out.

[Psudeonym]

It's a recent production Springfield Armory M1A i picked up used. Idk if they're supposed to have matching serial numbers or not, but it seemed noteworthy so i mentioned it.

Thanks GunDog and jarhead714, I made a query to SA, Ted Brown, Smith Enterprise out in AZ, and LRB and Fulton just for good measure. Someone else messaged me with a more local lead too.

In general its condition is a little poor for what it is, so i might end up just accepting the risk of ruining it and making it a project gun; but in that case i'd probably have to find somewhere where i could shoot it with a lanyard after any headspace/chamber changes.

[smoothy8500]

Idk if they're supposed to have matching serial numbers or not, but it seemed noteworthy so i mentioned it.

Here's some info as to what are "drawing numbers", basically spelling out what blueprint or spec sheet each part was assigned.

https://scott-duff.com/what-is-a-drawing-number/

[ar15barrels]

I've been tinkering with my M1A (late production springfield armory, purchased used, none of the serial numbers match) trying to find some accuracy, and i noticed that the op rod was hitting the piston waay off to the side, like 3-4 mm.

I tried nudging the op rod guide with a hammer, but i guess when this one was produced they really wanted to keep the op rod guides in place, i can see knurling or something cut in to the bolster that the op rod guide is pressed on, and the roll pin keeping it is really substantial, and really deep in to the barrel material.

I figured that if they went through so much trouble to keep the op rod guide in place, they must have set it's angle pretty carefully, so i checked the angle of the feed ramps, and they are off from center about 7 degrees counterclockwise.

in a way this makes sense, because my windage always had to be set way over to the right.

I don't know which direction you are referencing your clockwise or left/right from so I will ask a simpler question.
Is the barrel screwed in too far or not far enough?
The barrel has standard (right hand) threads.
If the gun is pointed at you and you were able to screw the barre into the receiver, you would be turning it clockwise.
Now with that in mind, is the barrel screwed in too far or not far enough?

7 degrees of barrel rotation would change headspace by about 0.002" which may or may not matter depending on which end of the spectrum the gun is on now.

[Psudeonym]

clockwise looking at the chamber from behind the stock. it's screwed too far in, which means the barrel will have to come out the front. This is why i'm kind of worried, if the barrel needed to screw in It seems like it wouldn't be hard to ream the chamber a bit deeper, but we can't un ream a chamber

[ar15barrels]

clockwise looking at the chamber from behind the stock. it's screwed too far in, which means the barrel will have to come out the front.
This is why i'm kind of worried, if the barrel needed to screw in It seems like it wouldn't be hard to ream the chamber a bit deeper, but we can't un ream a chamber

If you are behind the stock, looking at the chamber and the sight and gas block are clockwise from straight, the barrel needs to be screwed in some MORE.

[Psudeonym]

sorry yeah i misspoke, i meant counterclockwise

[ar15barrels]

sorry yeah i misspoke, i meant counterclockwise

Then the barrel needs to be removed, have the shoulder rolled down and then reinstalled to straight.
An alternative is to shim it 0.002" if you don't have a way to roll the shoulder.

[BrokerB]

Do not do business with SEI. Dirtbag of the first order.

[Psudeonym]

what's the dirt on them?

[kendog4570]

I have the tools and experience to address your issue. Headspace may be affected and not come in 7.62 NATO spec when barrel clocked correctly. No way to tell without inspecting it. If it is a new gun from SA send it back to them. It most likely will come back right.