M14 Receiver/Bolt wear

W

Wildcard91

Regular
Rating - 100%
14   0   0
I just received a used 2009 Norinco M305 today from a dealer selling it on consignment. The rifle seems to be in decent condition with a few requirements for shimming of the gas assembly and tightening the screw on the rear sights.

Upon closer inspection, I noticed some suspicious wear on the right side of the receiver behind the bolt lug. Is this indication of a larger problem, or is the rifle fine to keep and continue shooting. The last thing I want is a worn down receiver or a broken bolt from persistent firing, especially if I can take care of this with the warranty or return policy.

The wear is shiny and is slightly concave inwards as seen in the pics below. Thanks in advance for any input.

m305a.jpg


m305b.jpg

m305c.jpg
 
Last edited:
Just dug my 2009 out to look. It has approx 275 rds and that mark you show is not there. The parkerizing is showing light wear only in that area. It's almost like someone hit down on the op rod hard with something with the bolt roller about to go over the edge. of the But that dosen't make sense. Is there any strike marks on the high square part of the op rod handle which will sit over the bolt roller at that point in the cycle.

Sorry. Good luck.
 
I also have the same mark on my Norinco its a newer one with about 300 rounds through it , i contributed it to the misaligned op rod i found the last time i took it apart .

When i had the rifle apart the op rod wasnt lined up correctly with the gas piston it was off by about 3 mm and i noticed it was from the op rod guide on the barrel being misaligned , i nudged it over with a soft faced mallet and i cant see any riding anymore but i wont be able to confirm this until this weekend , im going to use a paint pen and see if it takes the paint off or leaves it alone.
 
What strikes me as odd is that I dont see anything weird on the underside of the bolt or oprod. The oprod is in perfect condition and has no signs of wear on the parkerizing. Since this is my first M305, I'll let you guys take a look at the bolt. Maybe you'll be able to spot something out of the ordinary.

Hope these extra large pictures will help.
bolt1.jpg


bolt2.jpg


bolt3.jpg


bolt4.jpg


Cheers
 
Fascinating! I have the same thing, and noticed it a while ago.

I figured it was a shortcoming in the machining/design department at Norinco; I bet if that spot on the receiver was radiused differently there wouldn't be a peening at that place... thoughts, anyone?

I've put around 800 rounds thru the gun so far, no problems, so I wouldn't keep from trips to the range, IMHO.
 
I got the same marks on my norc. I wouldn't worry about them too much the wear is small and seems to be just surface wear nothing to stop you from going to range.
 
I'm no M14/M306 expert... but I'll take an opinionated guess-timate anyways!!! :rolleyes:

If many people have it, what are the chances it is a metal hardness test location? I don't know who would do it, or what with, but that mark is too dang uniform: so thus my guess. :p

edit: I checked my Poly: no such mark, just a tiny bit of wear at the leadin edge where the bolt rolls down into place.
 
Last edited:
Aniest said:
I'm no M14/M306 expert... but I'll take an opinionated guess-timate anyways!!! :rolleyes:

If many people have it, what are the chances it is a metal hardness test location? I don't know who would do it, or what with, but that mark is too dang uniform: so thus my guess. :p

edit: I checked my Poly: no such mark, just a tiny bit of wear at the leadin edge where the bolt rolls down into place.
Click to expand...

Aniest it wouldn't be a good place to put a debit right where the roller runs to test hardness, no??
 
Also note that the rear of the bolt lug is also a little flatter and wider than the front in picture three. The pictures might not show it, but the top of the receiver is slightly indented beyond just the surface. I'm not to sure if that's a normal issue or not.
 
I have the same spot on my 09' Poly with 1100 rounds fired, but it was there after 300. I figured it was just the old war pig getting used to herself. :p

The comment above about missaligned oprod has me thinking. I have the roll pins to implement :canadaFlag: Hungry's :canadaFlag: roll pin within a roll pin to tighten up the guide, just have not done it yet.
 
That appears to be very much like the receiver damage that is seen with a Out of Battery detonation, however the mark in the receiver does not look severe enough, and the bolt appears to be ok. I would strongly suggest that you confirm proper headspace, Bolt lug contact, firing pin protrusion, firing pin hole diameter and receiver bridge operation as well as op rod spring length and condition. (I always recommend that on any M1, M14 type rifle).

I would also recommend that if all of the above checks out fine, that you fire only good quality NATO spec 7.62mmx51 ammo (not reloads) and see how it goes. Be sure that the rifle id properly lubricated.
 
Isn't it just the underside of the bolt near the roller lug rubbing on the reciever during the cycle of the action?

The wear spot on mine is very light, more just the parkerizing rubbing away than deforming the metal, so could it just be slight differences from rifle to rifle?
 
From your pictures the radius in that corner is almost non existent in your receiver as per a real M14.
There is a reason why the complete rifle is under $500, so its just the metal parts wearing/mating together. Any high spot, poor radius or anything not just right will chew itself off. So long as it is in tolerance and it functions and the high spots don't stop it from functioning, all is good.
 
Most Norinco bolts & oprods in Norinco (or poly for that matter) receivers will have that wear mark. It seems to be self-limiting based on the cam in the oprod.

In general, however, if you run a GI oprod and bolt, this wear patters either does not develop or does so to a lesser extent. I suspect a better oprod cam tolerance in GI oprods to be the difference.

Either way, don't worry about it. It's not down at the locking surface anyhow and if you ever wear out the receiver, a new rifle is only $500.
 
Mauser GDog said:
Isn't it just the underside of the bolt near the roller lug rubbing on the reciever during the cycle of the action?

The wear spot on mine is very light, more just the parkerizing rubbing away than deforming the metal, so could it just be slight differences from rifle to rifle?
Click to expand...

That is certainly what it looks like. The little rounded shoulder is rubbing on the receiver.
Has the rifle been kept properly greased?
 
I would say that if it was wear, you would see wear somewhere else on the corrosponding pieces. Mine has about 400 rounds through it, and some of the finish is worn off at this spot, but no real peening noted.
Mike
 
Well ill let you know im going to the range this weekend to try out some new ammo and some changes ive made , i just installed a usgi op rod , wolff springs , raunch tactical oprod guide , trued the op rod to the piston and put on a usgi flash suppressor .

Ill mark that spot with a paint pen and see if it wears it off during my range trip should be about 100 rnds total . if it doesnt wear at it , ill probably put my guess down on a slightly misaligned op rod , ill keep you updated.
 
Well i gave it a whirl today , 75 rounds and the paint went untouched , im going to attribute mine to an out of spec op rod , seeing as my peen mark is a little deeper with a bevel one side to suggest the bolt was riding over this one spot more than it should .

However i must say im not a fan of that MFS stuff either , my chamber and receiver look like someone blew red coloured cocaine all over it and the amount of unburnt powder is horrendous.
 
Kc.338Lp said:
Well i gave it a whirl today , 75 rounds and the paint went untouched , im going to attribute mine to an out of spec op rod , seeing as my peen mark is a little deeper with a bevel one side to suggest the bolt was riding over this one spot more than it should .

However i must say im not a fan of that MFS stuff either , my chamber and receiver look like someone blew red coloured cocaine all over it and the amount of unburnt powder is horrendous.
Click to expand...
I have been trying to warn people about this ammo. But I got every type of response from computer comando straight up to complete BSer. As for people looking for cheap great 308 ammo like me AE was the best bang 4 the $.
https://spreadsheets.google.com/spr...lr4thwOcExCX1ZOX2tMdno2MUVxSkp0eWdPQWc&gid=14
Can't beat $315 for 500 that is brass and boxer primed.
As for your orignal post I wouldn't worry about it. Uncle Mao says it cost to much for QC now day's ;)
 
You must log in or register to reply here.
Back
Top Bottom