loose op rod guide on norinco m-305

valmet762

Regular
EE Expired
Rating - 100%
2   0   0
I was just cleaning my rifle and noticed the op rod guide is slightly loose..

it moves a bit side to side, NOT front to back...

I cant remember if it was ever tight or not... is this normal?.. if not, can I shim it or is welding the only way to go?

any advice would be greatly appreciated.
 
Last edited:
The op-rod spring guide? If it's the stock flat one, the spring will be a looser fit.

Is this in a USGI fiberglass stock? If yes, you need to create a little tab out of JB weld or whatever to keep the op rod spring guide pin from sliding out while firing.

Marstar sells a replacement ORSG - I had one of the original Rooster33 ones, and was very happy with it. Makes it ring like a bell!
 
Last edited:
sorry, not the op rod guide with the spring on it.. the one attached to the barrel that the cylindrical part of the op rod slides thru.. i guess its not really called the op rod guide. it keeps the op rod in line with the gas piston.
 
Last edited:
Take the guide off and get a center punch and out some "Punch marks on the barrel where the guide goes.The punch marks will slightly raise the metal around the area and will make for a tighter fit for the op rod guide.
You could also have the barrel knurled around the op rod guide, either method works ,one just costs more than the other .

A new roll pin in the size 1/8X 3/4" long will help also !
I hope this helps !
 
Just finishing up a Hungry M14 Clinic had us all driving out those roll pins, putting a 1/8" (i think) roll pin in 1/2 way, then driving a 1/16" (i think) roll pin inside the 1/8" pin and driving them both flush.

This tightened up my guide solid!

PM hungry for more details.
 
No sweat operation. CGNutter ACE is sending me 100 pins of each necessary size. This is a very simple (read: big hammer) operation!!

We got yer BACK!! :evil:
 
I found the same problem on one of mine. I went out to the machineshop in the yard and low and behold my old man was clean out of any rollpins of usefull size. I decided to do a quick fix since I was shooting the next day as well. I drifted out the rollpin (it came out VERY easily, friction was barely holding it in there) then I took a tapered punch, and spread the pin open for about 7/8ths it's length. I placed the narrow end back in the hole, and used a brass punch to drift it back in, creating a interference fit. It locked up dead center and dead solid. I haven't thought about it since, I don't need to replace it, the thing will never move now. Chances are you have an undersized pin. DO NOT peen the barrel under the guide, there is no need for it and if you hit hard enough you could actually damage the bore.
 
Last edited:
DO NOT peen the barrel under the guide, there is no need for it and if you hit hard enough you could actually damage the bore.

punch peening or knurling the surface of the oprod guide location on the barrel is the accepted and practiced armourer and layman's method of National Match conditioning the oprod guide. I suppose if yer whacking away with a 10lbs sledge you might create a bore issue .... :D , seriously though, I perform this procedure with an automatic centerpunch, ya know the kind you hold in place and click with your thumb..... or the kind where you just press down and it spring punches. We are not talking about peening craters into the surface, one merely needs to distort it enough for a friction fit with the oprod guide.
I generally make 6 lines, running chamber to muzzle, of 6 punch marks per line.
a dab of red or blue loctite, slip and tap the guide into place, and install correct size new roll pin. assemble the action and ensure that the oprod is centered to the gas piston (not the cylinder... the actual piston). gently tap the oprod guide side to side as needed to align oprod with piston. once this has been done, set the action aside for 12 hours or so before cycling to allow for the loctite to set up.

It's important if one is going to match condition thier oprod guide , and "time" thier oprod/gas piston ....... ensure that the gas assembly itself is conditioned first ie: no play in gas assembly .... if it's loose side to side or front to back, deal with that before conditioning oprod guide.
 
thanks for the advice guys... I think i'll go with the new roll pin option.. I took it out to the range yesterday and it still shoots good.. i'm taking it deer hunting next week so i dont want to mess with it just in case I mess it up.. so when I get back I'll be doing the roll pin..

thanks again
 
Back
Top Bottom