M305 op rod alignment question

Lobster_pot

Lobster_pot

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Hey guys. Let start by saying I'm new to the m14/m305. So I might use the wrong part names.
I recently got my first m305. It's a shorty. Had it too the range once. Sighted the irons in. I thought it grouped really good at 50m.
Anyway my question is my op rod is out of alignment with the gas piston. So I stripped it and the op rod guide(?) is loose and moves a bit. How should I go about lining it up and securing it? Or should I even bother? I guess the pin is holding it then it was hit with a punch. Just line it up and hit it with a punch again? Bigger pin?

It actually looks worse when looking at it than it does in pic.
 
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A small carbide bit to cut out the stakes on one side and allow the roll pin to be punched out. There are a few ways to tighten it up including knurling and peening. You can buy a hand knurling tool, similar to a pipe cutter but with knurling rollers. Most just use a center punch and peen all around the oprod guide bearing surface. I like to scuff the surfaces before peening and use epoxy for extra strength. There's lots of ways to do it.
 
Ensure that your barrel is aligned before you stick that guide in place! It will save you a lot of pain down the road, ask me how I know.

If your barrel is actually in line then do the following:

Drive out the roll pin on the op rod guide.
Tap the op rod guide forward off it's raised mount part of the barrel where it's supposed to be.
Get a small center punch, using a hammer with the receiver in a vice or clamped well, do a line of center punches all around the area where the op rod guide sits when it's on the barrel.
Don't go too crazy or you will have to file the raised welts down to get the guide back on.
You want it to be a very tight fit but not have to smash the thing back on with the hammer of Thor.
The tricky part is going to be clamping the barrel again so that you can tap the op rod guide back in place.
I used a brass punch to get mine all the way back seated.
It still needed fine tuning so I assembled the op rod and gas block all back in place.
Then see if you need to tap the op rod guide left or right on the side of it. You will know as you will see reference your initial picture if the op rod is still out of alignment with your gas piston etc.
Once you get the op rod perfectly in line with the gas piston by hammering the op rod guide the way it needs to go, then hammer in the roll pin back into the op rod guide.

If the op rod guide will not go on with medium force, you may need to file down some of the welts you made on the barrel with the center punch. Just use a small flat file, go easy and keep trying to put the guide back on.
Some guys use blue loc-tite as well but I don't think it's necessary, I had to literally smash mine on with about 20-25 medium to heavy blows with the punch and hammer to get it fully seated to the rear lol.

Let us know how it goes but make sure your barrel is indexed first! lol If it isn't, correct that first before you stick that op rod guide on there good!
 
It depends on you.
If the rifle feeds and functions fine and the iron sights aren't so off index that you can still live with it and keep shooting it then you can follow the steps above and be good to go.
I'll say that mine was actually underindexed by enough that the front sight was visibly off on a cant.
I actualy had the op rod guide tig welded in 3 tiny little spots when I lined it up with a slightly underindexed barrel. The rifle shot very very well and I shot it like that for a very long time until the canted sight really started to annoy me.
Long story short, I had to file the welds down to break them then index the barrel, I bent my op rod guide in the process had to get a replacement etc etc
You may want to address the barrel index right away and do it right once instead of changing your mind and dealing with a lot of bulls**t after lol

Just my point of view learned the hard way ;)
 
If the rifle feeds fine, then there is generally no issue. Seeing as you are running the M14.ca mount and not the irons it really should be a non issue. Other than that if you do plan on shooting irons at sometime or another it wouldn't hurt to correct the indexing before.
 
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