Mosin nagant questions

Kingcuda

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I have a mosin nagant dated 1916 that was givin to me by my step father, he bought it in a crate and never fired it. I bought a box of 7.62x54r ammo and was going to give it a try but decided to wait after noticing a few things. First off, the end of the barrel seems much bigger than the bullet almost as if the rifle shoots a bigger round than the 7.62x54r, i did load the rifle and the rounds seemed to load and cycle just fine, there are no caliber markings on the gun and as far as I know the mosin nagant only used the 7.62x54r. The second concern ofnmine was that the bolt came out on its own. I know to take the bolt out you just pull the trigger back and pull the bolt out however if I do it just right and lift up on the bolt as I pull it back I can get it to come out without needing to pull the trigger to release it. I will add that the trigger does have a lot of back and forth play in it. I was really looking forward to finally be able to shoot this 100 year old rifle but figured safety should come first. Let me know what you all think about this
 
The muzzle issue could be from it being counterbored inside the first inch or two.
That was done on occasion as part of an arsenal refurb program to salvage barrels with extreme wear or rifling damage from cleaning at the muzzle end.

Look inside it with a light & see if the regular bore diameter resumes inside the barrel.

As for the bolt, something's obviously off kilter there.
Gunsmith, if nobody here follows with a solution.
Denis
 
Don't fire it until you get it looked at, something is either missing or worn out, you don't want that bolt in your forehead. I suspect the trigger group.

A 1916-dated import could have been in use during the Great War and Russian Civil War, from 1916-1921, then used again in Central Asia 1927-1929, and reissued during WWII 1940-45, so the odds are pretty good it's seen a great deal of wear and tear, in addition to probably not having matching parts anymore.
 
More than likely something is just gunked up in there from sitting around for 100 years. Take it apart, give it a good cleaning with firearms appropriate cleaners, look at the parts to see if anything looks amiss, put it back together with some appropriately applied firearms lube and see if the troubles are gone.

DPris answered the muzzle problem.
 
Thanks for the replies everyone. The muzzle issue makes sence because it does look like there are some tooling marks inside of it. Just need to figure out whats wrong with the trigger and why the bolt is able to come out on its own. I will be taking it apart today to take a look at things
 
The Mosin bolt stop is pretty simple, there is a nub on the trigger that rides in a slot on the back side of the bolt.

attachment.php


The round thing in the photo is what stops the bolt, it as actually part of the trigger. The square bit is the sear, which is part of the spring.

If either is excessively worn, or the trigger spring is bad/been messed with it could come right out.

If you hold the trigger forward (which the spring should be doing) does the bolt come out?

Does the bolt lock up tight, and does the trigger work when the rifle is cocked, or does it flop around? Is the trigger really light when dry firing?

On edit:
Trigger: https://www.gunpartscorp.com/Products/291930.htm
Sear/spring: https://www.gunpartscorp.com/ad/291990.htm (Don't know why they call it "Trigger Spring & Bolt Stop", because it is not the bolt stop. "Trigger & bolt stop spring" is a better description.
 

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he bought it in a crate and never fired it

With a 1916 date the rifle could be excessively worn. OR it could be some "preservative" still in the gun keeping things from working correctly.

Moisins are notorious for having been packed ..well preserved, and its not impossible your step father didn't do a completely thorough job cleaning it out.

The mechanisms are rugged and durable, but not indestructible. Full disassembly, thorough removal of the "cosmoline" and any other crud, inspection (visual appearance of parts) then a function check (empty).

A trip to a COMPETENT gunsmith is in order, to check the headspace, BEFORE FIRING.

To most of us, seeing a rifle in "the crate" gives us the impression it has been arsenal inspected, repaired if needed, and then stored. Often, this is the case. However it is also possible that the "arsenal refurbishment" was "DA! Grease good, put in box!" :rolleyes:
 
I know to take the bolt out you just pull the trigger back and pull the bolt out however if I do it just right and lift up on the bolt as I pull it back I can get it to come out without needing to pull the trigger to release it.

Trigger, sear, or both.
If the sear is bent, or if the end is worn, the end will not be pressing up tightly against the bottom of the action.

If the top of the "box" recess in the trigger, that rests against the top of the sear to keep it from dropping is worn, this could allow the bolt stop to drop too low.


Most likely though, the bolt stop at the top of the trigger, that rides in the slot/recess in the bolt connector and is supposed to catch the end of the recess (Emcon's picture) is worn, and you need a replacement trigger. Could also be that you have a defective or worn bolt connector where the end of the slot is worn and fails to catch the bolt stop.

If you can't narrow it down, post some pictures.
 
tobnpr said:
Most likely though, the bolt stop at the top of the trigger

Hey tobnpr, bet you a beer it is the sear/spring. :D

Because of this:
I will add that the trigger does have a lot of back and forth play in it.

Actually it is probably a combination of both.

If the sear/spring has the proper tension, the trigger should be held firmly in place. Well, maybe firmly is the wrong word, but it should have enough tension not to flop around.

Easy enough to test, hold the trigger forward and try and remove the bolt. If it comes out, it is probably the stop on top of the trigger, if it doesn't, it is probably the spring.

Another thing to look at, some people advocate putting a spacer between the sear/spring and the action, as a way to try in improve a heavy trigger. It screws to the bottom of the action just forward of the trigger. (You can see the tip of the screw in my photo, the circular thing at the left edge of the photo.

This post over on Gunboards shows how the trigger can be improved: http://forums.gunboards.com/showthread.php?163034-m91-30-and-shims&p=1278464#post1278464

Please note, I am not advocating doing anything listed, but his photos show what you can look for, and also shows pretty well what the Mosin Nagant trigger looks like under the wood, and gives you a good understanding of how it works.

And when you take it out of the stock to check it out, be really careful of the trigger pin. Those have a way of falling out and vanishing.

This problem does not mean the rifle is unsafe, unless the sear/spring is so bent or weak that the sear doesn't properly engage the cocking piece on the bolt. Is the trigger really light? If so, clear the rifle and cock it, then whack the side of it a couple times with the heel of your hand, as hard as you can. Also, bang the butt of the rifle on the floor a couple times.

As long is the sear doesn't release, it is probably safe to shoot.

As to the headspace, if it is a Soviet rework 91/30 it is most likely fine. You can buy the gauge set of Amazon for ~$50, or you can make them yourself using a nickel or a washer. The 7.62X54R headspaces on the rim, so the gauge is just a metal disk.

Here are the thicknesses, as reported by Yankee Engineering here

Military 7.62X54R MN
Go - .064
No-Go - .071
Field - .076

Really, all you need is the field gauge. If you are rebarreling a rifle, you would need go and no-go, but all you want to check is to see if it is under the max spec.

You need a metal disk that is .076" thick, I have heard of people using a nickel or a washer that is about the correct diameter. You can also do a quick and dirty headspace check on a rimmed cartridge by putting tape on the base of a cartridge or spent case, keep adding layers until it doesn;t close, then measure the thickness of the rim plus tape, and see if it is under the field dimension listed above. If you reload, you can also check with a deprimed case and a spent primer. Barely seat the primer, then chamber the case, and let the bolt seat the primer as far as it can go. Then measure the rim thickness plus primer protrusion. and compare with the field dimension.
 
Here are the thicknesses, as reported by Yankee Engineering here

Military 7.62X54R MN
Go - .064
No-Go - .071
Field - .076

What's interesting, is that the thread you linked went a bit further with "SAAMI" specs:

Military 7.62X54R MN
Go - .064
No-Go - .071
Field - .076

Saami 7.62X54R MN
Go - .064
No-Go - .068
Field - .071

Now, I never knew (and am still confused about this...) that SAAMI even has specs for the 54R.

They sure don't include it on their website:

http://saami.org/PubResources/CC_Drawings/C and C Dwgs - TOC - Rifle.pdf

This is a source of confusion for me.
I have a no-go, from PTG, that measures 675 tenths.
My go, from Okie, is 640 tenths.

The actual cartridge rim thickness design, per CIP, is 1.60 mm; or 64 thou.

3 thou, between go, and no go, just isn't correct. Should be around six thou at least, IMO.

I'd like to know where these "SAAMI" specs come from- and PTG's no-go which is only three thou different than the cartridge rim.

Just seems, plain "wrong", to me.
 
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This is a source of confusion for me.
I have a no-go, from PTG, that measures 675 tenths.
My go, from Okie, is 640 tenths.

675 tenths? Is that .0675"?

If so, it looks like your GO matches the GO specs for both listed above, and your NOGO is actually a little smaller than the SAMMI spec listed.

No idea where that SAMMI spec came from, although it is interesting that the SAMMI spec listed above seems to match the SAMMI drawing for .303 Brit. The rim thickness in the CIP specs also match between the two cartridges.

I don't see maximum chamber specs in the CIP drawing, do you? The only mention of headspace I see is note 4, "headspace on rim", and a dimension "Fe" of .1mm, which would be just under 4 thousandths. I don't see "Fe" on the drawing though. I may just not know what I am looking at.
 
On edit, just realized I can;t read, was looking at Q&A for the .303 Brit guage, which is right next to 54R. never mind.

I still don't see a listing for a SAMMI spec for 54r. The current document is ANSI/SAAMI Z299.4 - Centerfire Rifle - 2015, looking back in the internet archive, the previous version appears to be from 1992, and that doesn't list 54r either.
 
Hello,

Make sure the sear screw is tightened. If it is, a trigger slack spring would be an easy fix.

trspring2_sm.jpg


Sometimes the sears are bent wrong and allow that slack.

Regards,

Josh
 
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Thanks MM, now it's a pic for me as well. I was sure it was when I posted it.

I still have another tab open, and in that tab it's a link. Figure it's either a FireFox or TFL glitch.

Regards,

Josh
 
Now, I never knew (and am still confused about this...) that SAAMI even has specs for the 54R.

They sure don't include it on their website:

http://saami.org/PubResources/CC_Dra...0- Rifle.pdf

This is a source of confusion for me.
I have a no-go, from PTG, that measures 675 tenths.
My go, from Okie, is 640 tenths.

The actual cartridge rim thickness design, per CIP, is 1.60 mm; or 64 thou.

3 thou, between go, and no go, just isn't correct. Should be around six thou at least, IMO.

I'd like to know where these "SAAMI" specs come from- and PTG's no-go which is only three thou different than the cartridge rim.

Just seems, plain "wrong", to me.
The "free to the public" specifications available on the SAAMI website are incomplete and outdated.
If you don't see what you want, shoot them an email with the specific request. They'll likely ignore the request and not even respond; but, hey, it's worth trying, right? ... ;)


As for the PTG no-go only being 0.003" longer than the go gauge:
That's fairly typical with many cartridges. It may seem odd for well-worn, beaten, battered, and abused Mosins; but it's not an unusual headspace tolerance - especially when you're talking about a cartridge where only rim thickness matters.
 
SAAMI has a lot of specs they do not publish anymore. The 7.62x54R was produced in both rifles and ammunition in this country. Back before the internet, I called about chamber specs for a .22 HiPower I was working on. The guy on the phone (Sounded really young) said he never heard of it. I suspect it was an intern or maybe a janitor keeping an eye on the place over lunch. I believe SAAMI still lists a .303 Savage in their publications. Hard to understand why .22 HiPower is not listed. It could be they just drop certain cartridges that have disappeared.
 
As for the PTG no-go only being 0.003" longer than the go gauge:
That's fairly typical with many cartridges. It may seem odd for well-worn, beaten, battered, and abused Mosins; but it's not an unusual headspace tolerance - especially when you're talking about a cartridge where only rim thickness matters.

Not so, but please correct me if know of a cartridge with only .003 tolerance between min and max headspace...

In the rimmed/MN category, per SAAMI:

.45-70: .070 min, .077 max (.007)

.30-30: .063 min, .070 max (.007)

.303 British: .064 min, .071 max (.007)
 
That was done on occasion as part of an arsenal refurb program to salvage barrels with extreme wear or rifling damage from cleaning at the muzzle end.

Half true, Dennis.

During the arsenal refurbishing process, the Russians tended to counterbore almost anything, regardless of bore condition. Just because one's rifle is counterbored, does not necessarily mean that it had or still has a rough bore.
 
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