Counterboring a Mosin

sjohnston0311

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I have a 1932 Tula M91/30, typical post war Ukrainian refurb job. The rifling at the muzzle end of the bore is more or less completely worn out. I'd like to get it counterbored so that I can take it to the range.

Has anyone here had this done to their Mosin? Are there any gunsmith shop around that offer this service that you know of? I've found some DIY guides online, but I'm really not comfortable trying to do that myself.
 
Have you tried shooting it yet,I would see where she is shooting first before I spend the money.
I had one that you could almost shove the whole round down the muzzle,but it still was hitting
the plate at 100 yards.
 
I have a 1932 Tula M91/30, typical post war Ukrainian refurb job. The rifling at the muzzle end of the bore is more or less completely worn out. I'd like to get it counterbored so that I can take it to the range.

Has anyone here had this done to their Mosin? Are there any gunsmith shop around that offer this service that you know of? I've found some DIY guides online, but I'm really not comfortable trying to do that myself.
How good can you shoot a “good” rifle and ammo.
Have you exhausted all other “accuracy” gaining methods?

Put 10 rounds down range onto a SR target and see how she shoots.

Its possible the entire bore sucks and counter boring will only be money wasted.

A bore scope will reveal alot

Eventually I will test fire this poor rifle , just need to find some brass to load . I sold off my mosins and brass a while back as I had no love for them
 
Have you tried shooting it yet,I would see where she is shooting first before I spend the money.
I had one that you could almost shove the whole round down the muzzle,but it still was hitting
the plate at 100 yards.
It's been so long since I've shot it, I can't even remember the details other than I wasn't satisfied. Perhaps I should take it to the range one of these days to see if it's really necessary. I have tried the bullet test and the round goes in almost all the way.
 
It's been so long since I've shot it, I can't even remember the details other than I wasn't satisfied. Perhaps I should take it to the range one of these days to see if it's really necessary. I have tried the bullet test and the round goes in almost all the way.
My gut says if you where not happy then you wont be after counter boring it.
Hows the stock fit, trigger , can you see the sights well enough?
 
I have a 1932 Tula M91/30, typical post war Ukrainian refurb job. The rifling at the muzzle end of the bore is more or less completely worn out. I'd like to get it counterbored so that I can take it to the range.

Has anyone here had this done to their Mosin? Are there any gunsmith shop around that offer this service that you know of? I've found some DIY guides online, but I'm really not comfortable trying to do that myself.
Unless you can locate a gunsmith that has counter bored Milsurps before just be careful. I saw one person suggest just a get a hand drill!!!!!!!! YIKES! I also suggest purchasing a crowning tool. They are very easy to use and can make a big difference in accuracy.
 
Unless you can locate a gunsmith that has counter bored Milsurps before just be careful. I saw one person suggest just a get a hand drill!!!!!!!! YIKES! I also suggest purchasing a crowning tool. They are very easy to use and can make a big difference in accuracy.
If the bore is as bad as he describes a fresh crown will just look pretty.
And the DIY crown tools rely on a pilot bushing so tou would need a decent selection of guide bushings. Starts to get expensive when your buying a range of stepped sizes.
 
Considering counterboring my recent bnz43 purchase that can barely hit paper. All but swallows an 8mm round. Was going to ask the gunsmith when I pick up the front sight fixed VZ-24.
t
 

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I think before any counter boring is done a good smith machinist should check the bore size completely . No sense in counter boring if the actual bore is worn.
Bullet test is a weak test. Get a 7.62mm for mosin pin gauge at least.
 
Considering counterboring my recent bnz43 purchase that can barely hit paper. All but swallows an 8mm round. Was going to ask the gunsmith when I pick up the front sight fixed VZ-24.
t
Bore looks a little crusty
Whats the bore size on a 8mm? 311-312” ?

What ammo , action screws tight?
Hows head space ? Do you have a throat erosion gauge for mauser?

Anyway with out actually gauging the bore with pin/plug gauges say from .299” through .320” in increments of .001” you really have no idea where to end the counter bore. Ideally you want to counter bore to the tightest portion of the bore.
 
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None of the above. Shots were ‘50s and ‘70s Yugo. Screws tight. Barrel is original German. May try a box of new PPU first.
t
 
Seems overkill for nearly 100 year old bores.
t
Would be cool though,
Counter boring a old rifle would be pissing money away IMHO.
I would definitely try better ammo.
I had zero luck with any of the surplus crap 8mm.
Looks like you had a sideways impact on one target.
When you put a jag and patch down the bore does your cleaning rod spin?
 
I have several Mosins that have been counterbored, All done during the refurb process, most I have never fired so not sure how well they shoot, It should not be a difficult or expensive to do.
 
I have several Mosins that have been counterbored, All done during the refurb process, most I have never fired so not sure how well they shoot, It should not be a difficult or expensive to do.
I think this is highly dependent on how it’s done and who you bring it to you.
I’m sure a lot of us can modify a drill press to have enough room underneath it and someway to mount the barrel and have Addit and it will be fine. But then again you can bring it to a gunsmith and have them check it up in LA that’s not gonna be cheap. Oh I think it’s one of those things that if you’re going to have done you’re gonna have to find someone you know and he’ll do it for you at a decent price.

Now just because a state run arsenal decided to counterbore tens of thousands of rifles versus replacing the barrels was just a cost cutting alternative
 
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