Mosin Nagant

Ac1d0v3r1d3 · April 6, 2009, 07:27 PM

Sorry for the fuzzy pics, I'm trying to figure out my new camera
As you can see, there was an issue with my mosin. That flat spot on the rim is from the extractor slipping off as the case got stuck in the chamber upon firing.
Once the round had fired the bolt stuck and i had to hammer it open. Then of course the casing was stuck, and i was out in the woods with no ram rod. When i rammed it out last night i noticed that the primer wasn't in the casing.
My Mosin is a model 1944.

And the head stamp on the case is
*
3 10
50

Anyone have an idea as to what happened?

JasonJ · April 6, 2009, 07:44 PM

check the headspace.. might not be enough room in the chamber

paladin-34 · April 6, 2009, 08:04 PM

7.62 x 54R primers are pritty shallow so it would not surprise me to loose it while pounding the case out. have you been using metal cased ammo in the gun? the varnish comes off in the chamber and this happens. spend some time cleaning the chamber, it may have some well baked on varnish from previous owners also.

Joe

Flumph · April 6, 2009, 08:15 PM

On a bolt action rifle (or maybe all rifles, for that matter), when the powder charge explodes in the casing, the primer actually deseats and flies back against the bolt. The gas pressure recoil pushes the casing back against the bolt and into the extractor, reseating the primer. The distance that the round is allowed to fly back by the bolt (called the headspace) needs to be within a certain range for the spent casing to seat in the extractor properly.

This, at least, is my understanding of how headspace works. Problems with it are fairly common in milsurp rifles.

Sounds to me like your headspace is too far; then again, i'm no gunsmith. Check it or have it checked. If you reload your own ammo, i think you can adjust the case length according to the error in your headspace (but i might be mistaken).

Good luck!

Ac1d0v3r1d3 · April 6, 2009, 09:01 PM

So how do i check the head space and what should it be?
I've fired close to 1000 rounds (all brass) out of it in the last 2 years or so and this is the first time I've had a problem like this. So i doubt its from build up from lacquer in the chamber. Also when i bought it, it was "new". Lots of cosmoline but little wear inside the barrel.

Thanks for the quick responses
-Chris

ferg · April 6, 2009, 10:02 PM

After a 1000 rds in two years, all brass, I'd call this a fluke and not worry about it. If had happened with any frequency, then I'd worry.

kyle1974 · April 6, 2009, 10:16 PM

look for a button on your camera that has a little flower... that's the macro setting. turn it on, and you can take those close up shots

**44 AMP** · April 6, 2009, 11:00 PM

Brass cased or not, you are shooting milsurp ammo, right?

You could just have gotten a bad (overpressure) round. Milsurp ammo, especially in East Bloc calibers can be of dubious origin and quality control.

Jimro · April 7, 2009, 12:10 AM

acid overide in 1337?

I guess it has a better ring than "crash burn", but srsly "Hackers" wasn't that good.

Jimro

Ac1d0v3r1d3 · April 7, 2009, 10:31 AM

Jimro! Right on, your the first person to actually know what my sn was about. I know the movie really just sucked, but I've been Ac1d0v3r1d3 for almost 10 years, so why quit now?

Yes, all the ammo that I've shot in my mosin has been surplus. And I've had some problems with it before, split cases and the like, but never a problem that may have been caused by my rifle.
I'm not entirely sure where my current lot of ammo is from. If i recall correctly is was 1970's manufacture. Maybe South Africa?
Thanks again
-Chris

srt 10 jimbo · April 7, 2009, 11:12 AM

Just got my M91/30 Last Saturday. Have not fired it yet, cant get ammo.

Volucris · April 7, 2009, 03:22 PM

Aimsurplus has tons of ammo available...

WeedWacker · April 7, 2009, 03:36 PM

Quote:

Sounds to me like your headspace is too far

Not to direct this question at you but for everyone, if it were a headspace

issue being too long, what about too short? I have some silver bear SP's that

seem to fit a little tighter in the chamber than some of the modern brass cased

FMJ (and SP) rounds I use. Almost afraid to shoot them because it takes some

hand work to lock the bolt although it does lock. (Rifle is a M91/59 BTW)

paladin-34 · April 7, 2009, 07:14 PM

You said you had some split cases. Assuming you see the same splitting I do, from the neck of the case down into the first third of the case. If so those splits exist before the round is fired and can be found by side loading the projectile with your thumb as you hold the brass in your hand. Any projectile that moves in the neck during this test has a split case. The problem with split cases is the tiny bits of brass that may be left in the gun when the case splits. Which could have been the cause of your jam.
Clean it good and shoot it again.

Joe

Jimro · April 7, 2009, 07:15 PM

Quote:

your the first person to actually know what my sn was about. I know the movie really just sucked, but I've been Ac1d0v3r1d3 for almost 10 years, so why quit now?

I went with the handle "Yojimbo" until some version of Final Fantasy or other introduce my generation to the Ronin for hire as a summon. Just wasn't the same when people thought I was based on a video game instead of the film that inspired "A Fistful of Dollars".

Nothing like an insider pop culture reference. When did we get old?

Jimro

**44 AMP** · April 7, 2009, 11:58 PM

Is that the 7.62x54R is a rimmed cartridge. The "headspace" of the rifle is a measure of the space available for the case rim to fit in, and has nothing to do with the size or shape of the rest of the chamber.

Unlike a rimless round, such as the .308 (7.62x51mm/7.62 NATO) which headspaces on the dimension from the base to a point on the case shoulder, checking the headspace on a rimmed round doesn't tell you anything about the rest of the chamber. If the chamber shoulder is too far forward, but the rim dimensions are good, it would pass a check with a headpsace gauge, and still split cases on firing.

The good news is, that if your chamber is excessive or undersize, you will have problems with virtually all the ammo you shoot, not just a round or two.

To be certain of your rifle's chamber, a chamber cast must be made, and then measured against factory specs.

This can be done at home, with a little practice and the right materials, but a good gunsmith should be able to do this, and can check other things (such as the headspace) as well.

Considering all the ammo you have shot, and only had this happen once, I still vote for a bad (overpressure) round.

Ac1d0v3r1d3 · April 8, 2009, 12:34 PM

Quote:

You said you had some split cases. Assuming you see the same splitting I do, from the neck of the case down into the first third of the case. If so those splits exist before the round is fired and can be found by side loading the projectile with your thumb as you hold the brass in your hand. Any projectile that moves in the neck during this test has a split case. The problem with split cases is the tiny bits of brass that may be left in the gun when the case splits. Which could have been the cause of your jam.
Clean it good and shoot it again.

Since, in this case, my ammo is older than i am i generally check each round before i load it. I've found some unfired rounds that had a split from the neck down the side of the case. Those of course i don't load into the gun. But the splits that I've had in fired cases have all been near the base of the case, about 1/3 to 1/4 of the way up.

Jimro, funny, i think of yojimbo as a pocket knife. But yeah i hear what your saying.

paladin-34 · April 8, 2009, 09:09 PM

the chamber needs to be checked. it could just be dirt, or brass peaces creating a gap between the case and chamber (most likely). I’ld scrub the chamber with a well fit brass brush.

Joe

YODA308 · April 9, 2009, 01:26 AM

Cant tell from the pics but check the brass that you removed with the cleaning rod, if it has scratches along the length of the case you could have rust in the chamber. living in seattle i expect you have more than ordinary humidity.rust could be the problem especially if you put the rifle into a case while it was still warm.

April 6, 2009, 07:27 PM	#1
Ac1d0v3r1d3 Senior Member Join Date: April 19, 2005 Location: Goldendale, Washington Posts: 439	Mosin Nagant Sorry for the fuzzy pics, I'm trying to figure out my new camera As you can see, there was an issue with my mosin. That flat spot on the rim is from the extractor slipping off as the case got stuck in the chamber upon firing. Once the round had fired the bolt stuck and i had to hammer it open. Then of course the casing was stuck, and i was out in the woods with no ram rod. When i rammed it out last night i noticed that the primer wasn't in the casing. My Mosin is a model 1944. And the head stamp on the case is * 3 10 50 Anyone have an idea as to what happened? __________________ I aint the worlds best writer nor the best speller But when i believe in something i'm the loudest yeller. Woody Guthrie

April 6, 2009, 08:04 PM	#3
paladin-34 Senior Member Join Date: December 12, 2006 Posts: 177	7.62 x 54R primers are pritty shallow so it would not surprise me to loose it while pounding the case out. have you been using metal cased ammo in the gun? the varnish comes off in the chamber and this happens. spend some time cleaning the chamber, it may have some well baked on varnish from previous owners also. Joe __________________ New York: where we import politicians but no standard cap mag.s. 7 rounds in a 10 round mag, andy will be running for president soon.

April 6, 2009, 09:01 PM	#5
Ac1d0v3r1d3 Senior Member Join Date: April 19, 2005 Location: Goldendale, Washington Posts: 439	So how do i check the head space and what should it be? I've fired close to 1000 rounds (all brass) out of it in the last 2 years or so and this is the first time I've had a problem like this. So i doubt its from build up from lacquer in the chamber. Also when i bought it, it was "new". Lots of cosmoline but little wear inside the barrel. Thanks for the quick responses -Chris __________________ I aint the worlds best writer nor the best speller But when i believe in something i'm the loudest yeller. Woody Guthrie

April 6, 2009, 10:02 PM	#6
ferg Senior Member Join Date: January 15, 2006 Posts: 135	After a 1000 rds in two years, all brass, I'd call this a fluke and not worry about it. If had happened with any frequency, then I'd worry. __________________ Some idiots are too busy knowing it all to ever learn anything

April 6, 2009, 11:00 PM	#8
44 AMP Staff Join Date: March 11, 2006 Location: Upper US Posts: 28,835	Where is the ammo from? Brass cased or not, you are shooting milsurp ammo, right? You could just have gotten a bad (overpressure) round. Milsurp ammo, especially in East Bloc calibers can be of dubious origin and quality control. __________________ All else being equal (and it almost never is) bigger bullets tend to work better.

April 6, 2009, 07:44 PM	#2
JasonJ Senior Member Join Date: January 17, 2007 Posts: 151	check the headspace.. might not be enough room in the chamber

April 6, 2009, 08:15 PM	#4
Flumph Senior Member Join Date: March 8, 2009 Location: Dallas, Texas Posts: 139	On a bolt action rifle (or maybe all rifles, for that matter), when the powder charge explodes in the casing, the primer actually deseats and flies back against the bolt. The gas pressure recoil pushes the casing back against the bolt and into the extractor, reseating the primer. The distance that the round is allowed to fly back by the bolt (called the headspace) needs to be within a certain range for the spent casing to seat in the extractor properly. This, at least, is my understanding of how headspace works. Problems with it are fairly common in milsurp rifles. Sounds to me like your headspace is too far; then again, i'm no gunsmith. Check it or have it checked. If you reload your own ammo, i think you can adjust the case length according to the error in your headspace (but i might be mistaken). Good luck!

April 6, 2009, 10:16 PM	#7
kyle1974 Junior member Join Date: November 23, 2008 Location: Texas Posts: 254	look for a button on your camera that has a little flower... that's the macro setting. turn it on, and you can take those close up shots

April 7, 2009, 12:10 AM	#9
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	acid overide in 1337? I guess it has a better ring than "crash burn", but srsly "Hackers" wasn't that good. Jimro __________________ Machine guns are awesome until you have to carry one.

April 7, 2009, 10:31 AM	#10
Ac1d0v3r1d3 Senior Member Join Date: April 19, 2005 Location: Goldendale, Washington Posts: 439	Jimro! Right on, your the first person to actually know what my sn was about. I know the movie really just sucked, but I've been Ac1d0v3r1d3 for almost 10 years, so why quit now? Yes, all the ammo that I've shot in my mosin has been surplus. And I've had some problems with it before, split cases and the like, but never a problem that may have been caused by my rifle. I'm not entirely sure where my current lot of ammo is from. If i recall correctly is was 1970's manufacture. Maybe South Africa? Thanks again -Chris __________________ I aint the worlds best writer nor the best speller But when i believe in something i'm the loudest yeller. Woody Guthrie

April 7, 2009, 11:12 AM	#11
srt 10 jimbo Senior Member Join Date: September 10, 2008 Location: Fort Lauderdale Posts: 955	Just got my M91/30 Last Saturday. Have not fired it yet, cant get ammo.

April 7, 2009, 03:22 PM	#12
Volucris Senior Member Join Date: January 30, 2009 Posts: 293	Aimsurplus has tons of ammo available... __________________ "From my cold, dead hands!" - Charlton Heston

April 7, 2009, 07:14 PM	#14
paladin-34 Senior Member Join Date: December 12, 2006 Posts: 177	You said you had some split cases. Assuming you see the same splitting I do, from the neck of the case down into the first third of the case. If so those splits exist before the round is fired and can be found by side loading the projectile with your thumb as you hold the brass in your hand. Any projectile that moves in the neck during this test has a split case. The problem with split cases is the tiny bits of brass that may be left in the gun when the case splits. Which could have been the cause of your jam. Clean it good and shoot it again. Joe __________________ New York: where we import politicians but no standard cap mag.s. 7 rounds in a 10 round mag, andy will be running for president soon.

April 7, 2009, 11:58 PM	#16
44 AMP Staff Join Date: March 11, 2006 Location: Upper US Posts: 28,835	The probolem with headspace Is that the 7.62x54R is a rimmed cartridge. The "headspace" of the rifle is a measure of the space available for the case rim to fit in, and has nothing to do with the size or shape of the rest of the chamber. Unlike a rimless round, such as the .308 (7.62x51mm/7.62 NATO) which headspaces on the dimension from the base to a point on the case shoulder, checking the headspace on a rimmed round doesn't tell you anything about the rest of the chamber. If the chamber shoulder is too far forward, but the rim dimensions are good, it would pass a check with a headpsace gauge, and still split cases on firing. The good news is, that if your chamber is excessive or undersize, you will have problems with virtually all the ammo you shoot, not just a round or two. To be certain of your rifle's chamber, a chamber cast must be made, and then measured against factory specs. This can be done at home, with a little practice and the right materials, but a good gunsmith should be able to do this, and can check other things (such as the headspace) as well. Considering all the ammo you have shot, and only had this happen once, I still vote for a bad (overpressure) round. __________________ All else being equal (and it almost never is) bigger bullets tend to work better.

April 8, 2009, 09:09 PM	#18
paladin-34 Senior Member Join Date: December 12, 2006 Posts: 177	the chamber needs to be checked. it could just be dirt, or brass peaces creating a gap between the case and chamber (most likely). I’ld scrub the chamber with a well fit brass brush. Joe __________________ New York: where we import politicians but no standard cap mag.s. 7 rounds in a 10 round mag, andy will be running for president soon.

April 9, 2009, 01:26 AM	#19
YODA308 Member Join Date: March 27, 2009 Location: PHOENIX/ARIZONA Posts: 39	Cant tell from the pics but check the brass that you removed with the cleaning rod, if it has scratches along the length of the case you could have rust in the chamber. living in seattle i expect you have more than ordinary humidity.rust could be the problem especially if you put the rifle into a case while it was still warm.