M1A alignment issue

[Polar Express]

I recently purchased a new M1A 'standard' with the black plastic stock. I bought it with the full intention to install the action into a SAGE stock, which I purchased. When putting it all together, I noticed something, and I am concerned about, so I thought I'd put up a post and see what soultions (if any) are needed, or recomended. It went together the first time very smoothly. No binding, no trouble at all. The guide block certainly appeared to be right on. I'm pretty mechanical, and there was no indication of a fitment issue. So, I was a bit surprised when I reinstalled the op-rod, and it was not inline with the piston. At first, I thought it was the op-rod, since I noticed the non-alignment issue upon installing the op-rod. Now that I have taken some more time to really look at it, the op-rod appears to be dead-on in line with the barrel. It's the gas block/piston housing that appears to be off. This does not make any sense to me, since the gas block is actually aligned with splines, and then held in place with the figure-8 retainer. I used the right shim combo to require just a bit of compression by the figure-8 retainer before installing the gas plug, per the directions from SAGE.

I'll try and explain how its 'off': with the barrel and receiver removed, from the stock and sitting on my bench upside down (op-rod up), and looking down the barrel, with the receiver towards my chest and muzzle away from me, the gas block appears to be rotated clockwise just a tad. I never fired the rifle before installing the SAGE stock, and now I feel like a fool for not measuring or noticing the allignment even COULD have been off in the original configureation. But, seeing as how it's orientation is splined, I can't see how it could have been straighter from the factory. The piston does NOT appear to strike the op-rod at an angle, that is to say, it appears to strike it along the same axis, but it is clearly off-center of the op-rod. And, as best as I can tell, the op-rod is in fact correctly located, and it's the piston housing that is off.

I have some pics, and I'm working on trying to get them attached.

What suggestions or ideas would you have? Is this even a concern?

Thank you all for taking the time to share your wisdom,

PE

 

[lipadj46]

Upload your pics to photobucket.com and then photobucket will provide the IMG code to copy and paste into your message here.

How far off is it? Does the rifle operate properly? Sometimes the gas cylinders/gas cylinder locks need to be shimmed a bit to line up exactly. Springfield will take care of it for you under warranty.

 

[Polar Express]

Ok, I'm trying to get this to show some images. Unfortunately, they are all a bit blurry, please forgive me, I am not a photographer. In response to Lipadj46, the gas block/piston housing seems like it's 'clocked' if that term makes any sense. Its not much, as the photo shows, but adding or removing shims won't alter the condition I am referring to. The position is controlled by the 'splines' that are machined into the threads on the barrel.

Let's see if these work.

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I have NOT fired the gun, I don't want to risk damage if something is wrong.

 

[Jason_G]

I think that's normal.

Jason

 

[Polar Express]

have you seen a bunch that look like this? Im just nervous about misalignment of high-velocity mechanical parts.

 

[Candiru]

That looks a bit off. It could be caused by the barrel being incorrectly torqued. Did the rifle come with a tag that listed its headspace?

The actual alignment itself shouldn't cause an issue with respect to functioning. If, when you fire it, the point of impact is significantly off, that would support the theory that the barrel is misaligned.

 

[wayne in boca]

Could be an undertimed barrel,or could be an optical illusion.Or you might be crazy.Shoot it and see if the sights will work with minimal adjustment (set at mechanical zero,front sight centered on its base,rear sight set to center).Simple matter to tighten the barrel a tad if it needs it.

 

[Silverado6x6]

http://www.m14tfl.com/upload/index.php

Go to that link, they know everything, I use it for getting the real dope on my M1A.

 

[Polar Express]

OK, Thanks for the input and ideas so far.

Yes, it came with the tag with the headspace measurement on it. The tag from SA lists it as 1.631.

I put the barrel and action on as flat as a surface as I have in my home. Its not a machining environment with a layout table, its just my kitchen table.

I first started but making sure the action is level, by setting the sight block on a parallel bar. Then, I took the other parallel bar, and touched it to both the outside of the barrel, and the outside of the gas piston cylinder. Since they are NOT the same OD, that's not a problem, as long as they have equal angles from the vertical. With the action inverted, the bars should form a very tight "V". they don't. The one on the side of the charging handle, (on the left looking down the barrel from the action, with the assy. inverted) is straight up and down, with the off-side being at a noticeable angle.

Next I installed the op-rod, and did the same thing. It's off to the same direction, but just a hair. Not really enough to make me think the barrel is not installed properly. It may be within spec, but I don't know. I would like it to be as close to perfect as possible, to give me the longest life possible out of the wearable parts. It sure looks to me like the problem is a warped piston housing.

The divider between the feed ramps is already at about 5:45, and since the barrel is a 'righty-tighty', I can't really cheat and minimize this by tightening the barrel just a tad.

I don't think firing this thing would be a good idea. Anyone have other thoughts?

I'm thinking I have a bad product. What do you guys think?

thanks again,

PE

 

[Candiru]

Sounds like the barrel is torqued wrong. The raised section between the feed ramps should be at 6 o'clock. If the headspace is good it's probably safe to fire, but there might be issues with long-term durability due to the gas piston/op-rod misalignment. I'd call up SA and tell them about it.

 

[Macgille]

Firing it probably won't hurt anything but the accuracy will be rotten. It will act like a bent op rod and is a pain in the A--.

 

[nicholst55]

Since Springfield has a lifetime warranty, they should fix it without any questions. I'd suggest calling them and carefully explaining the situation. Your barrel is not correctly 'timed,' but they may say that it's within their specs.

IIRC, the Army only allowed a .060" tolerance when barreling M14s; no telling what Springfield allows, and they will tell you that you DO NOT own an M14, but rather an M1A. Different animal, and they get to make their own rules.

 

[Polar Express]

update

Well, I'd better update you all with where this went. Per Silverado6x6, I went to the M1A forum. I posted my situation there and got some interesting replies.

The short summary, is most of it was my error. :banghead: I HATE saying that.

I put one parallel bar on the bottom side of the SAGE block, and the other on the under side of the action, then looked down the assembly. The SAGE op-rod guide block was just a hair off. When I say 'hair', I mean a wispy ultra-thin hair. First of all, I did not think it was possible to get that misaligned because of the roll-pin that holds it in place. Second, once I figured out it was off, I did not think it could have made as much of a difference as it did. So I corrected the alignment of the guide block. Not a big deal to do that. This did remove most of the misalignment, but not all. So, using the same parallel bars, I held the action inverted, with a bar on each side of the gas block, going up and down, touching both the outside of the piston housing, and barrel. They have different OD's, but that's OK, as long as each bar is equally angled from the vertical. They were not, you can see this with the naked eye. This confirms the gas block/piston housing is indeed off, and if I were to try to tighten the barrel just a tad to line it up properly, then the front sights would not be at 12:00, and the feed ramp divider would be farther away from 6:00.

I don't like this level of misalignment from any factory, but I suspect it's within the spec from SAI. I'll give them a call this week, and see if I can get some info out of them.

It may be of note, (I think it is), but the flat spot on the bottom of the chamber portion of the barrel is NOT inline with the underside of the action. And, the divider between the feed ramps is at about 5:45. I plan on mentioning that to SAI when we talk, and see what they say.

Thanks again for all who helped, I sure feel like I learned a lot with this. (it doesn't mean I'm smart, just smarter than I was)

PE