A .316 cast boolit in .313 bore

[chaplaincolby]

I have some .316 dia. 200 gr. cast boolits I obtained for an Mosin 91/30 with a worn bore. I have obtained a T-53 rifle with a good bore that slugs at .313. I would like to test a few cast rounds in the T-53. Would it be safe to shoot the .316 boolits in the .313 bore with a small (about 17 grains H4227) charge for some subsonic rounds?

[btroj]

It would be fine. The bore will size them down just fine.

[Hickok]

I say as long as the loaded round chambers, no being too tight in the neck and throat, and you start low and work up your powder charge you will be good to go.

[rintinglen]

^^^What he said. Pressures don't really begin to build until the boolit gets to be about .004-.005, and even then the effect is incremental, not exponential. Depending entirely on the gun, you may find that accuracy is better than that provided by skinnier boolits. But regardless, a mild load will still be a mild load, albeit perhaps slightly higher pressure. Were you loading to the redline, it might be a different matter.

[Motor]

I say as long as the loaded round chambers, no being too tight in the neck and throat, and you start low and work up your powder charge you will be good to go.

I was thinking the same thing as this. I use a Lee TL 160gr in my Mosin Nagant(s) I use it as cast which is between .313 and .3135 I use these in 3, M39 Finns that mearure from .3105 to .3115 and they work very well.

You'll likely be happy with the results, if they chamber ok, and want to use them all the time.

Motor

[newrib]

All of the above, although I have not shot the 316299 from any of my Mosins yet I do use that big bullet in Lee-Enfields with .313 to .316 bores and about the same load. They do shoot great !

[chaplaincolby]

Thanks guy's ! I had already tested a round to see if it would chamber, it did. I was thinking the boolits would work fine, but in reloading a question asked as an ounce of prevention is worth a ton of medical care.

[JeffinNZ]

17gr will not be subsonic. Will put you around 1500fps.

[303Guy]

Hi Jeff.


17gr will not be subsonic. Will put you around 1500fps.Just what I was thinking. I used 4227 under 208gr boolits (fat boolits in a fat bore) and by the time you get the powder to burn clean you'll be up there somewhere. Nice velocity and very mild recoil. I would use Dacron to position the powder, about half a grain up to maybe one grain. It'll sound like an overgrown 22lr high velocity.

The only issue with shooting a fat boolit in a normal bore is base distortion. A gas check rebate will eliminate base distortion and it may not be a major issue anyway. As has been said, pressure will rise a little which may be what you need to burn that powder clean.

[chaplaincolby]

303 Guy, my condolences on loosing your son, my daughter was also born in 1986, I cannot imagine what it would be like to loose her. My prayers are with you.

[303Guy]

Thank you, chaplaincolby​.