M14 Forum banner
1 - 20 of 28 Posts

·
Registered
Joined
·
363 Posts
Discussion Starter · #1 ·
To give a little background I had an m14 built a little while back and apart from the op rod the gun has been outstanding. As it was my first m14 I didn't really know what to look for in the surplus GI parts and bought what was advertised as an excellent condition op rod - turns out it was not.

This first came to my attention when m118lr ammo popped the op rod right out of its track - turned out the tab was well out of spec. Had it re-welded by Columbus machine works who did an excellent job. and dropped in a sadlak nm op rod spring guide

Unfortunately - this revealed a new problem - every few shots, the op rod catches on the diss-assembly notch and holds the bolt open on a loaded mag and has to be pushed down to chamber the next cartridge.

I'm guessing this means my op rod is slightly bent - though I couldn't really tell where - I tested it with the spring and guide removed and it still pushes up into the diss-assembly notch when I pull it back.


Anyway, I wanted to find out if I am correct in this diagnosis and if so what my options are?

Any help is greatly appreciated.
 

·
Forever Remembered - RIP
Joined
·
2,141 Posts
did you drop in a fresh new shiny op rod spring to go with the spring guide?

maybe start there...

but you raise a question I have...

about how far the op rod should travel....

should it make it back to the dismount notch under normal firing?
 

·
Registered
Joined
·
363 Posts
Discussion Starter · #4 ·
It passes the tilt test other than hanging up on the notch - there is a small hangup when the tab is about halfway past the start of the notch but I have to be barely tilting the rifle for that to slow it down

- the spring only has less than 500 rounds on it and I don't currently have any other springs to try.

The op rod guide appears strait on the barrel.

Also, I don't know how far the op rod should travel - but that does make an interesting question.
 

·
Registered
Joined
·
1,703 Posts
Help us help you

The make of the receiver, condition of the receiver, timing of the barrel, alignment of the gas cylinder on the barrel compared to the op rod tip, pictures of the components, and a list of other parts, such as bolt.
Is the bolt roller making contact with the receiver just below the front of the sight platform?
Pictures assembled and disassembled, pics of the cam in the op rod, pics of the tab, pics of the barrel extension showing the feed ramps, compare how much wiggle the op rod has in its track.

It can be one thing or several stacked up to cause this.

If any place can help it is on this Forum.

Jim
 

·
Registered
Joined
·
363 Posts
Discussion Starter · #7 ·
The make of the receiver, condition of the receiver, timing of the barrel, alignment of the gas cylinder on the barrel compared to the op rod tip, pictures of the components, and a list of other parts, such as bolt.
Is the bolt roller making contact with the receiver just below the front of the sight platform?
Pictures assembled and disassembled, pics of the cam in the op rod, pics of the tab, pics of the barrel extension showing the feed ramps, compare how much wiggle the op rod has in its track.

It can be one thing or several stacked up to cause this.

If any place can help it is on this Forum.

Jim
Okay, gonna try not to miss anything here.

-The receiver is SEI - purchased new for the build
-The barrel is correctly timed as far as I can tell
-The op rod tip is centered on the gas cylinder
-The bolt is an old Springfield USGI
-op rod is Winchester USGI as is trigger group
-I have both a sadlak nm and USGI op rod guides - when replicating the issue at home it seemed less pronounced with the GI op rod guide - will need to confirm this at the range.
-there is a little wiggle in the op rod - the top moves back and forth a bit
-the bolt roller does not appear to contact the receiver

I'll work on getting some pics
 

·
Registered
Joined
·
468 Posts
I was told not to shoot the M118LR because it might be a little to hot for the op-rod. Advised not told ! Was I advised wrong?
This is totally wrong as the only ammo we used to test M14EBR-RIs is M118LR. I have personally shot 20K rounds of M118LR through M14s and can assure you that there is no problem whatsoever with its use. It is the prefered ammo used in AFG bythe Army.DISHOUT
 

·
Registered
Joined
·
999 Posts
With no spring, rod guide or bolt, run the rod all the way to the rear.

Look to see if the gap between the rod and the shelf is constant along the whole shelf lenth.

This is an indicator of straightness.

It should be parallel to the shelf and ideally resting on the shelf.
 

·
Registered
Joined
·
363 Posts
Discussion Starter · #10 ·
Okay, took some pics - hopefully everything's here!

Barrel timing


Bolt closed w/op rod


Take down notch


op rod wiggle - held against receiver


op rod wiggle - pulled away from receiver


Op rod tab - un-parked from re-weld - not wear








Receiver minus op rod


Bolt roller


Bolt forward


Op rod in forward position


Op rod in intermediate position


op rod in rearward position / diss-assembly notch






Gas cylinder / op rod alignment


 

·
Registered
Joined
·
363 Posts
Discussion Starter · #12 ·
With no spring, rod guide or bolt, run the rod all the way to the rear.

Look to see if the gap between the rod and the shelf is constant along the whole shelf lenth.

This is an indicator of straightness.

It should be parallel to the shelf and ideally resting on the shelf.
- it angles upward towards the back end - you can see in the pics i just posted - tried it w/out the bolt and same result.


-my bad - i was writing this response when you posted - didn't see it till after
 

·
Registered
Joined
·
363 Posts
Discussion Starter · #14 ·
Rod is bent, you can see in pics
Yeah that's what I figured - as this already needed re-welding am I better off just getting a new SEI forged op rod and if so, should I get one and see if it drops in first or do I just need to send the gun in and have andy fix it?
 

·
Registered
Joined
·
999 Posts
Yeah that's what I figured - as this already needed re-welding am I better off just getting a new SEI forged op rod and if so, should I get one and see if it drops in first or do I just need to send the gun in and have andy fix it?

That one can be straightened out. Any new rod correctly made should drop right in and pass the visual test I described. The rest is your decision.
 
  • Like
Reactions: Mikey

·
Registered
Joined
·
363 Posts
Discussion Starter · #18 ·
to have it straiten do they need the whole rifle or just the op rod?

And who all can I send this to to get fixed?
 

·
Registered
Joined
·
999 Posts
to have it bent do they need the whole rifle or just the op rod?
best fitted to one it is going in at this point, barrel and rcvr are all that would be needed.

if everything was to spec then rod only.

company policy may require something else
 

·
Registered
Joined
·
363 Posts
Discussion Starter · #20 ·
is there anyone in Illinois who can fix the op rod? - I just hate to have to ship the rifle - very very expensive
 
1 - 20 of 28 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top