i was going to reload for a rifle chambered for this caliber and i found something that concerns me. the groove diameter measures 0.316". the closest i am going to be able to get to this is to use 0.311" bullets unless i can find some 0.316s.

1. does anyone know where 0.316" bullets can be found?

2. if i use the 0.311" bullets will they upset adequately to seal the bore?

I had a beautiful M38, exactly as you describe. The grooves were .316". My solution was to sell it at a loss, to open up space in my gun cabinet. I wasn't interested in a wall-hanger, and I didn't see any way it was going to be a shooter.

Not what you want to hear... but I couldn't find a better solution.

OTH, my Finnish M39's slug a .3105", and are superb shooters.

Hi Bill, I don't know what jacketed bullets might be available but you can always shoot cast bullets. You might be able to find a place to buy them if you arent into bullet casting, (which I assume you are not or you would have thought of that already) . It makes for cheap shooting and you do not have to give up anything in terms of accuracy. Hope this helps, Joe S

Woodleigh makes .312 and .318 bullets. And as already stated, you could cast your own.

Best check the neck diameter first, just because the bore is oversize dosn't mean that the chamber neck is. Spec. calls for a .308 dia bullet, but .311 and .312 bullets often work acceptably in the larger barrels (after checking to ensure that the case neck has enough room to release the bullet).

Denton: when you say your m-39 slugged at .3105", do you mean the land diameter or the groove diameter? my 39 has a land diameter of 0.308, but the groove diameter is 0.316.

Tailgunner: you are exactly correct. i am certain that the bore is oversize by design. also, the Finnish 39 has a reputation as being very accurate. keeping this in mind, i suppose that the .311 or .312 bullets must upset enough to seal off the bore.

this is the only rifle i have ever noticed where the bullet diameter and the bore diameter are so far apart and it just caught my attention as being odd. i have checked Czech and Russian surplus, Russian hunting, and Winchester FMJ rounds and they all check at 0.311". i should've done this checking before i posted this topic. anyway, thanks for the input form each of you.

Bill...

.3015 is the groove diameter of the Finns. My M44 has a groove diameter of .3110. They all digest .311 bullets quite happily.

The Mosins do vary quite a lot, and many have particularly deep grooves.

This is a caliber that I personally really enjoy. The Finns are completely capable as deer/elk guns, and the little M44 is about the handiest "behind the pickup seat", bang around, all purpose rifle you can find.

My one concession was putting Mojo sights on the Finn. My old eyes just can't see the rear sight anymore, and the Mojo fixes that. It's still an iron sight, and I can put 'em in a 2" circle at 100 yards with that arrangement. No wonder the Finns did so well against the Russians!

You won't find any "standard" production brand .316"'s! Maybe MOLOC has them or would be willing to make you some! Try this: get a couple jacketed .318" (8x57 Mauser "J" bore size) bullets. See if these will drop freely into your fired cases before they are resized. If they do, you can shoot these. 0.002" over groove won't hurt a thing, as long as the cartridge case mouth will freely release the bullet when fired! I have some Argentine 7.65X54mm FM ammo that has .314" bullets, which would work, but they are 185-grain FMJ's! My Argentine Mauser shoots .308" bullets better than these .314"'s!



Another option, as mentioned above, is the cast bullet. They can be driven over 2500 FPS in your rifle, if you use a good gas-check design and make them from the right metal, such as heat-treated wheelweights! Shoot them as-cast, if possible, and make them about .318" also! Use large charges of slow powders to get high cast bullet velocities. If you accelerate them gradually, they shoot more accurately. Plus, a case full of powder is better than a powder charge that wanders around and is in a different place inside the case for each shot.