[Bugshank]

I bought a Sadlak NM spring guide and installed it on my JRA Rockola. When I bring the charging handle back the action gets hung up to the point it locks to the rear and I have to do a very forceful sort of M1 palm slap to send the charging handle back home.

Experimenting a bit, I finally found the rubbed portion on my NM spring guide where it's abrading against something on the inside of the op rod. So, it seems to be a simple enough fix, but what should I use? Have any of you had to do this? I have a drill. It really only should be a few seconds worth of work, but I'm curious as to what type of attachment will work best.

If anybody can offer any insights that'd be great.

 

[Greyson]

I bought a Sadlak NM spring guide and installed it on my JRA Rockola. When I bring the charging handle back the action gets hung up to the point it locks to the rear and I have to do a very forceful sort of M1 palm slap to send the charging handle back home.

Experimenting a bit, I finally found the rubbed portion on my NM spring guide where it's abrading against something on the inside of the op rod. So, it seems to be a simple enough fix, but what should I use? Have any of you had to do this? I have a drill. It really only should be a few seconds worth of work, but I'm curious as to what type of attachment will work best.

If anybody can offer any insights that'd be great.

First, I would get a small bright flashlight and look in there to see what it is you're trying to remove. That will influence the method.
Generally, I would advize getting a long piece of wooden dowelrod and cutting a lengthwise slit in the end a couple inches long. Cut a strip of abbrasive paper with a reasonable grit size like 180 or 220 and insert the end of the strip, wrap around and around to near inside diameter of oprod tube, in the opposite direction you will spin the dowel with a drill. Insert and work it until polished smooth. Won't hurt to polish the entire length of the inside to help the spring ride smoothly. Clean out, spray inside with CLP, lightly grease spring and guide.....

 

[danthman114]

Pictures

 

[Bugshank]

First, I would get a small bright flashlight and look in there to see what it is you're trying to remove. That will influence the method.

Literally the title, man...

 

[Bugshank]

Pictures

Can't right now, but they're not really needed anyway. And at any rate how am I supposed to cram a flashlight and camera against the same hole and take a usable photo?

Burr inside op-rod.
Need to polish out.
My question-- what tool and attachment would you use?

 

[Greyson]

Can't right now, but they're not really needed anyway. And at any rate how am I supposed to cram a flashlight and camera against the same hole and take a usable photo?

Burr inside op-rod.
Need to polish out.
My question-- what tool and attachment would you use?

Read my post.

 

[Bugshank]

Read my post.

Just checked back, see the edit now. Thank you.

 

[Ted Brown]

The problem is that the inside diameter of the tube is .474+.008". They don't make drill bits that size or anywhere close. You will have to find a grinding or sanding drum that will fit and probably an extension of some kind to get it in deep enough. The rod is a hardened part so it would be difficult to remove a dent if that is the problem. You may need a new op rod in that case.

 

[DstRflMn645]

Bugshank,

Are you sure that the spring guide is moving freely in the slot in the receiver and the slot in the guide? Always best to do any modification on the cheapest part. If it does not it can bind in the op-rod.

John

 

[nf1e]

The op rod guide only touches the inside of the spring. If you are seeing an abrasion on the guide, check the spring itself. One possibility that we have run into a few times over the years is a Chinese spring getting into the program. They have a smaller ID and will do exactly what you describe. Make sure your spring is in spec for a starter.

Semper Fi
Art

 

[Earthquake]

Do you have a Chinese op rod by chance? They are a little smaller inside. If its just a burr I would do like Greyson said and get a dowel or piece of tubing and cut a slot in the end and insert a piece of Emory paper or plumbers tape in the 180-200 grit range and spin away, don't try to reverse it once you start it or it will jam up.
Make sure to grease it up after your done because you are removing the Parkerizing and it could rust.

Casey

Edit
I did not see Arts post on Chinese parts before I posted.

 

[Lazerus2000]

Unless there is an actual DENT,
or a crack in the joint of a two piece US GI op rod,
which should be visible from out side,
there should be no burrs or constrictions inside the op rod tube for the spring to catch on.

If the spring is the usual GI ID/OD, then it will slide smoothly over a US made round op rod spring guide. However, as ART pointed out, the Chinese springs, with slightly different [ metric equivalent ] wire diameter, and ID/OD, may bind on the OP ROD SPRING GUIDE. So far, I have never had any op rod spring bind on the INSIDE of the op rod, binding always occurs on the op rod spring guide.

PS: Many Canadian companies manufacture ROUND op rod spring guides specifically to fit BOTH Chinese and US type of springs.

So,
as usual with any M14 troubleshooting and repair issues,
start with the simplest/least expensive fix first.

Before grinding anything;
Try a different spring, or go back to the less constrictive flat op rod spring guide.
OR,
if you absolutely feel the need to change some thing,
just chuck the op rod spring guide in a drill and POLISH the op rod spring guide rather than drill out the op rod