Moscow match question

[arachn'auquébec]

Hi!

I made and shot 20 moscow match by replacing the .310 148 gr. bullets from my cz surplus 7.62X54r with .310 150gr bullets from speer. They worked just as well as the original cz surplus, producing about 6'' groups a 100 yards with my 1944 M44. As you can see, accuracy could be better...

I slugged my bore this morning at .315''. So .310 bullets are a bit slack in this bore, I guess this could be one of the reasons for this kind of accuracy.

I see hornady has .312 150gr bullets. Will I be able to seat them in the surplus steel cases made for .310 bullets?

Thanks for any help! I just want to make sure before I buy 100 bullets...

 

[sunray]

"...moscow match..." AKA Mexican match.
Steel cases are not reloadable. Steel is not elastic like brass is. Doesn't resize properly and can damage your dies. Usually, but not always, berdan primed too. Two primer flash holes means berdan. Berdan primers are virtually unavailable.
The .312" bullets won't be much better. You'll still have a 3 thou gap. You might be able to get a .315" mold for cast bullets. The BP guys might be able to help with that.
Steve, at .303british.com, seasonally, makes 200 grain .314" jacketed bullets. Mostly for the .303 British though. Don't think I'd want to shoot a 200 grain bullet out of a carbine though.

 

[arachn'auquébec]

I know steel cases are not reloadable, I am not exactly trying to reload here, but just to make reasonably accurate cheap hunting ammo out of cheap millitary surplus...

From what I understood of a previous thread about steel cases, steel is more elastic than brass, but brass is more ductile.

You are right that I don't really want to load 200 gr bullets in my carbine. I have a project for a 180gr bullet, but thats probably the max I would load, and that would be way enough for moose anyway...and fun to experiment...

My question is more about bullet diameter. Will the neck be able to stretch enough, like 0.001-0.003'' more or will I just ruin the bullets.

 

[cosmic]

You should be fine - just chamfer the mouths, if not done already. Also, check to make sure the is no interference at the neck with a loaded cartridge in the chamber - unlikely, but why take a chance?

 

[arachn'auquébec]

What do you mean by interference at the neck? and by chamfer the mouths?

 

[rnbra-shooter]

What do you mean by interference at the neck?

If you use a larger diameter bullet, the diameter of the ammunition at the case neck will increase by this amount.

It is important that the case fit freely into the rifle's chamber. In particular, the neck must not be "gripped" or "squeezed" by the chamber. When the cartridge fires, it is important that the bullet not be prevented from leaving the case. "Interference" would happen if the diameter of the cartridge's neck was larger than the diameter of the neck portion of the chamber.

You can measure the outside diameter of a fired case (it will have stretched during firing). If this diameter is larger than the diameter of your loaded ammo, then everything is good. Ordinarily, the diameter of a fired case will be .010"-ish larger than a round of loaded ammo.

and by chamfer the mouths?

This means to cut an angle at the case mouth. It will make seating a bullet easier. A sharp case mouth can "shave" or cut off bits of a bullet when seating it. Look up a "case mouth chamfering tool" to see what is used.