M1 Garand- Failure to Fire

[Marnoot]

I was at the range yesterday with my M1, which I had had no problems with ever since replacing the op-spring some time ago. Yesterday, a couple times when the trigger was pulled the hammer could be heard releasing, but the round didn't fire and closer inspection revealed either a *very* light, or no firing-pin mark at all on the primer. It felt and sounded as though the hammer released properly, but the pin never struck the primer. After taking out the trigger group and cocking and releasing the hammer a few times, then putting it back together it worked fine for a few rounds, then had the same problem again.
I'm at a loss as to what could be the problem. The firing pin moves freely, things are properly greased/lubricated, the hammer spring doesn't seem weak, it sounded/felt like it released, but there just weren't any marks on the primer. Any ideas?

Thanks!

Greg

 

[mattw]

I have a springfield M1A and admittedly am no expert but:

1.) What kind of ammo were you using? maybe the primers were seated to far into the casing.

2.) Did you check out the bolt? Maybe the firing pin or firing pin spring.

3.) I am guessing that everything is locked up when you try to fire, since you said you replaced the op rod spring and that loading the rifle requires that you either slam the bolt home or release it to slam home itself.

my guess without seeing it is: ammo or bolt-related problems.

 

[Steve in PA]

1) Make sure the bolt is seating fully.

2) When was the last time (if ever) you've cleaned the bolt, inside and out?

3) How are you storing the rifle? Not with the trigger cocked, correct?

 

[Marnoot]

The bolt's clean as a whistle and properly lubed, and when it fired after tinkering with it it was with the same rounds that had no firing pin marks on them before, so I doubt it's ammo specific. After firing they had regular, appropriately deep pin marks on the primers. Cycling was normal as far as I could tell when both rounds were fed. I suppose it's possible the bolt wasn't fully in battery both times, but they were mid-clip rounds, and I've never had a problem with the rifle not fully cycling before. But if it was slightly out of battery, wouldn't that have resulted in an out-of-battery firing rather than no pin strike?

Edit:
I completely disassembled and cleaned the bolt a couple range trips ago, and it's plenty clean. I store it uncocked.

 

[Vern Humphrey]

It's possible that you had a slight out-of-battery condition. The bolt cams the firing pin back as it rotates to unlock, and when locking, if it is almost, but not quite in battery, some of the force of the hammer blow will be absorbed by the cam face on the rear of the bolt.

Clean and inspect the cam recess in the operating rod hump, and clean the bolt lug recesses in the receiver. Be sure the bolt and hump are properly lubricated.

 

[oneshooter]

You might also pull the bolt and check if the firing pin is intact. A broken pin will strike soft.

Oneshooter
Livin in Texas

 

[ACP230]

If the firing pin broke it might give inconsistant ignition.
I broke one dry firing a couple years ago. Sometimes the firing pin would drop all the way and sometimes it wouldn't. I didn't actually fire the gun with the pin broken, but I could tell something was different from the sound it made when it failed to dry fire correctly.

The tip off to what was wrong was when I pulled the bolt and the back half of the firing pin fell out of it.

Could be something else, of course, but the pin might be something to check.

 

[Dienekes]

What ammo are you using? I too suspect out-of-battery--just enough so the web bridge is not allowing the firing pin to travel forward (as designed for such cases). A case too long at the shoulder or in need of trimming, or a bit oversized could give you slight out-of-battery.

The M1/M14 series of rifles want the ctg. in spec in every dimension. Once I got very serious about proper trimming and gauging all cases and rounds I had no problems whatsoever.

The Kuhnhausen book is excellent on this and all other things related to these rifles.

 

[Marnoot]

I'm shooting Korean surplus, Poonsang, lot PS-2-090. I'll caliper a few random ones to see if they're out of spec at all. I check and trim as necessary when reloading, but for now I'm shooting the surplus stuff.

Edit: I checked out several from a few different boxes, they're all within spec as far as I can tell. Case length on the ones I measured were between 2.488" and 2.491".

 

[mattw]

That sounds really wierd, what could keep it from not locking up fully when they were mid-clip rounds? I've never seen that before.