M305 failure to fire

[Dereck]

Went to the range yesterday to try out my new Smith Enterprises scope mount with Leupold 6x42, switched from Arms 18 due to case ejecting issue. Shot 10 rounds of American Eagle 150 gr .308 with no trouble, switched to South African Surplus and the first two rounds fired, but each empty case were caught between bolt and scope mount when ejecting.

Shot a few more American Eagle, then my friend tried shooting the South African again, had three failure to fires in a row. I then tried the American Eagle, same thing. The primer on all these rounds was only slightly dented, compared to my earlier cases.

Dismantled the rifle at home, had a bolt disassembly tool and managed to take bolt apart with no mishaps and sprayed bolt down good with WD-40. I washed out 3 or 4 pieces of metal, each approx. 2x3mm in diameter. The firing pin was not fully going down before this, likely causing the shallow primer indents and failure to fire issue. Now the firing pin seats all the way down in the bolt (sorry guys, not too up on correct terminology), just like my new Springfield bolt does which I am comparing it to.

I have inspected the bolt as good as I can, and it and the firing pin all appear A-OK. The small, squashed pieces of metal must be pieces of primer, as best as I can figure. I may have had a little excess grease on action and bolt raceways, but I don't think any found it's way onto the bolt face or into the chamber.

All parts on my Norinco M-305 are original except Rooster Op rod spring guide and a recoil buffer(which I am going to remove after reading bad things about them on here-the recoil buffer, that is).
I have shot a variety of mil surp through the rifle, Norinco, Hirtzenberg, Porteguese etc, and limited my factory ammo to American Eagle 150 gr and Winchester, Federal 168 gr match. Anybody have an experience like this, or any other insight would be great. I am going to get a couple USGI chrome firing pins and compare my used Norinco one to them before attempting bolt reassembly and firing again.

 

[girlsgunsandfastbikes]

Sounds like you've probably found your issues.....go back out there with a cleaned rifle and try it again.


GG&FB

 

[Juster]

You can try to shoot a pencil out the barrel to see if the firing pin actually moves. I remember someone on guard duty getting a pencil though the back, closely followed by a 9mm bullet, so it needs to be unloaded.
My M305 failure to fire was caused by loosened epoxy bedding in the trigger .
Anyway, what GG&FB said.

 

[bingo1010]

what bad things about recoil buffers might you be referring to?

 

[Dereck]

shok buffer

OK, here is the long winded explanation.... by putting in a buffer you have made shorter the distance the op rod handle can move backwards. The M-14 as with the M1 Garand design relys on the op rod and the rear of the reciever as well as the compression of the op rod spring to "Take up the shock" of the impact of the bolt moving to the rear. By making that distance shorter you are relying on only the op rod to take that force, at the roller bearing area. It is not designed to take that kind of force and will give it up way before it is supposed to. Now think about this, your bolt is in fast forward backwards and breaks right at the roller bearing area, if you are right handed, it takes off your right ear on it's way back past the reciever, if your left handed, well I think you get the point. Putting in a buffer excelerates wear it does not make it less. It does seem to lesson the impact and therefore the force of the impact but it is really just making your gun break sooner than it should. As for eating scopes, take a look at what the U.S. army had on thier XM-21's during the Viet nam war, just a cheap comercial hunting scope slightly modified for service use, any cheap scope made today is better than some of the most expensive glass made 30 years ago!! Perhaps you should reconsider your choice in glass. I know of shooters who have great luck with the straight 10 power 3200 series from Bushnell. With a good mount, say an ARMS 18, not a cheap copy of a good mount you should have a scope last and not be eaten.
Just my 2 cents, hope this helps by way of explaining.

Scott

I have never used a "Shok Buff" in any of my M14 type rifles.Those that I have seen use them all had feeding issues at one time or another.

I also never had a problem with any of my M14s "eating" scopes.This is why I spend the coin and buy top Quality optics.

I have used a Bushnell 3200 10X on my M14s and that is the "cheapest" piece of glass I would buy.All my other M14 optics Have been Leupold MK4s or Aimpoint Comp M2s.

SKBY.

The buffers are safe to use if they have been fitted to the rifle. The bolt must be allowed to contact the rear of the receiver but the op-rod does not have to contact the front. As long as the bolt impacts the rear and there is still play in the bolt roller/op-rod interface at full rear travel nothing will break.

The problem with them, is that people think it is just a simple drop in part that will work on all rifles. The differences in the various runs of M14S/M305's and production tolerances can cause failures if they are not installed/fitted properly. I have been installing them in M14S/M305 rifles since International first started bringing them into the country and have yet to see any problems with them when they have been fitted to the rifle. I even have a mold for making my own and my buffers have been in over 80 rifles including a target rifle that is about to finish off it's second barrel with no parts failures or FTF.

Fitted properly they work quite well.
-Mudpuppy

-This is the info I read in the past posts on this forum. I have cut and pasted thiese posts so others may benefit from them without doing a search. I thank the authors for their contribution and hope they don't mind me re-posting it.
Anyone have any further info on using/not using a shok buffer on their M-14?
-Dereck

 

[Plinker]

Dereck:

Do you have any of your fired brass? Check the primer areas. You'll probably see small bits of metal missing.

I have had this problem, and written posts about it previously. SOME of the Norinco bolts have too much clearance at the bolt face, around the tip of the firing pin. Basically, the hole is too big or the firing pin diameter is too small, or both. When the gun fires, primer metal extrudes into the gap between the pin and the bolt-face, and gets stuck down in the firing pin channel. Replacing your firing pin with a USGI pin will reduce the pin-to-hole clearance by approx 50%. This completely solved the problem for me.

I have also seen some Norinco firing pins that have irregular tips. This makes the problem worse. Again, replacing the firing pin will solve the problem.