Moisan Nagant reloading

[zacharoo]

I have a Model 59 Moisan. The barrel slugs out at .310dia. Is it dangerous to load with Hornady .312 dia. bullets. I use siera 125 and 150 Pro hunters. My best load is with 180 gr. Remington .310 dia. bullets. I have some one who is willing to give me some Hornady bullets in 150 and 170?? grain . But they are .312 dia.  I could get 200+ of each but am worried about pressure. HELP!!!
Zacharoo

[shot1]

If your bore truly is .310 I personally would not try to shoot .312 bullets in it.  .311 is as large as I would go. Hornady makes a 174 gr FMJ Spirtzer bullet that is .3105 diameter that should shoot very accurately in your bore for target work.

[Larry Gibson]

If you work up the load with .312 bullets it will not be dangerous.  I shoot lots of .312 Hornady's in my MNs all the time and my other .31s, even the .310 ones.  I also regularly shoot .310 bullets in my .30s.  The .312 bullet will be sized down to .310 in one bearing length of travel.  This happens very early in the time/pressure curve.  Once sized down it is the same as any other .310 bullet for the rest of the barrel.  I know this because I pressure test such in numerous rifles including the MN with .312 bullets.   Just work up the load as you should.  The real potential problem with MNs, depending on the cases used is will the cartridge loaded with the .312 bullet chamber as some won't.
 
Larry Gibson

[JIMinPHX]

If an old MN slugs at .310", there is a good chance that you still have some 50+ year old cosmoline inside that barrel.  That stuff can be a bear to remove sometimes & can also be hard to identify as something other than barrel steel.