Advice on Mosin caliber conversion

[M. Sage]

i have a 30-06 to 7.62x39 adapter. but my 30-06 is just too much fun and so accurate that i havent bothered installing it. its a semi-permanent adapter tho.

I know .30-06 is .308 diameter, I thought 7.62x39 is .310...?

A Google search later, and I'm looking at .310-.311 for 7.62x39.

[762cavalier]

You are correct Mike, but the x39 bullet (.310) will swage down in the 30-06 barrel.

[AJAX22]

how hard would it be to make a chamber ream?

could i use empty brass and coat them with an abrasive and lap out a chamber that way?

To make one that was safe and easy to use would be a real Pita if you don't have a setup to grind tools (and not by hand, I mean the real machine to do proper grinding)

far cheaper to buy the premade one.

Unless of course you wanted to get into the reamer making buisness... then it might be possible to turn a proffit

You might be able to rough cut the chamber and then lap it to final specification, but it would always be slightly undersized.

the brass will always deform more than the barrel will

[ar15barrels]

I haven't come across a proper 7.62x25 chamber ream yet though (I haven't been looking very hard)

I think I have a 30 mauser reamer that's so close to a 7.62x25 that it should work for a simple chamber adapter.

[762cavalier]

yeah the 30 mauser case is just .001 fatter and a little shorter and uses the same shoulder angle. probably close enough to work.

[alpha_romeo_XV]

[sloguy]

i found the papers that came with my adapter from years ago and now that i know the company name i found their website.

http://www.mcace.com/rifleinserts.html

http://www.mcace.com/shotguninserts.htm

http://www.mcace.com/adapters.htm

they do custom stuff. if we all email em they might develop one as a regular product.

[gunn]

Here's another chamber adapter company. I found them when someone mentioned that they have a convertor for 32ACP in a 7.5 Swiss case.

In this situation, they have a 32ACP to 7.62x54R for $20 shipped. I called in early january and found out that while they do not have a website, the son has taken over the business and they still operate at the same mailing address.

Here's my post (with ordering forms)

http://theswissriflesdotcommessageboard.yuku.com/reply/24786/t/Question-regarding-32ACP-adapter-for-the-K-31.html#reply-24786