Question: Springfield M1A Op Rod noise

[edSky]

Hi, I just got an M1A a few weeks ago and have been familiarizing myself with it before taking it to the range. The other day I noticed that when I moved the op rod back and forth there was a "buzzing" sound. Is this normal?

I took a look and the front end of the op rod tube is knurled. The op rod guide appears to be canted slightly, which is probably causing the two to rub. Again, is this working the way it's supposed to be working? Is it typical of the Springfield M1A?

Thanks.

 

[lipadj46]

The op rod guide is pretty much supposed to sit at a 90 degree angle to the bottom of the receiver. How is it canted? Do you have it in upside down? Btw no this does not sound normal.

 

[General Geoff]

Pictures would be helpful..

 

[Retro]

If that is the case, do not fire this rifle until it is looked at by a gunsmith. If the rod is really canted/tilted, it may fracture during firing and may even damage your receiver or bend your barrel.

 

[edSky]

The op rod guide is pretty much supposed to sit at a 90 degree angle to the bottom of the receiver. How is it canted? Do you have it in upside down? Btw no this does not sound normal.

I didn't measure it yet, just eyeballed it. It's brand new from Springfield, so I hope it's not upside down. It looks like it's angled forward. Looking at the barrel from the right (muzzle to the right, bolt to the left), it looks like the front edge of the guide is up (or closer to the op rod) and the trailing edge id down (and farther away).

If it is off, it is only off by a thousandth or so. I think this is what's causing the points on the knurling to rub, making the zipping noise.

(I'll see if I can post a picture later in the week, possibly Wednesday evening.)

 

[lipadj46]

The flat side of the op rod guide faces up (towards the action) or in other words the flat side rests against the action, but that does sound like the problem if you are talking canted forward. I will have to look at my M1A when I get home to see what you are talking about, too tired cannot conceptualize it.

Lightly grease your spring and op rod guide too, that may help the sound. I will post later if anything occurs to me when I look at my rifle.

 

[edSky]

It's the 8-shaped op rod barrel guide, not the op rod spring guide.

I'll try and get a picture up in a day or so.

 

[lipadj46]

Do you mean the gas cylinder lock?

http://www.e-gunparts.com/productschem.asp?chrMasterModel=2070zM14

 

[pgeleven]

+1 - get it to a gunsmith for a one over.

and may even damage your receiver or bend your barrel.

lest not forget the damage it could do to you and those around you should that thing decide to become a party favor

 

[lipadj46]

There is not much damage that can be caused by what he is describing besides mechanical damage to the piston, gas cylinder or op-rod.

It is a new M1A and SAI has a lifetime warranty so just call them and send it back. They pay shipping both ways.

 

[edSky]

I heard back from Springfield and they said it is normal and will disappear with use.

It's just the peaks of the knurling rubbing the op rod barrel guide. It will seat itself with use, and proper inspections and lubrication is in order. And as mentioned above, the warranty should cover it.

 

[lipadj46]

It's just the peaks of the knurling rubbing the op rod barrel guide. It will seat itself with use

The knurling on what part?

 

[edSky]

the front end of the op rod tube is knurled

Maybe it's specific to the MA9222, but the forward end of the op rod tube is knurled, like a file (or the checkered grip of a 1911).