Howdy folks,

I am in need of a smith and there are none in my area that are competant. I have a Siamese mauser whose bolt face was improperly modified for the 45-70 rim. It appears to have been milled and is way oversize. It will need to be tig welded and machined properly.

I am in no hurry and can be without for a year if necessary. I know how backed up most of you are. I live in south Texas.

Andy

drewhenry Before you go and spend a bunch of money maybe you should check to see if your boltface was opened up for the 348 Win case. The 348 case is larger than the 45-70 but fits the Siamese magazine and is the basis of some powerful rounds in 375,416 and 458 cal all on an improved 348 case.

I don't know any smiths, but my Dad has one of the Siamese mausers Navy Arms built years ago. I feeds and functions very well you if you need any measurements or pictures and don't mind waiting until I can get to his place to measure or take pictures just PM me.

Looks like it is time for a chamber casting. A 348 rim fits perfectly, but the barrel is marked 45-70. What kind of wildcats are 458 cal and built on a 348 case? Wasn't the 348 the original case used to develop the 475 and 500 Linebaugh?

Andy

Andy,

If you’re concerned that the 348 Winchester rim fit the bolt face I wouldn’t be.

The CIP/SAAMI maximum rim diameter specification for the 348 Winchester is .6098” vis-à-vis .6079” for the 45-70 Govt; this is only a .0019” difference between the two cartridges.

I had communication earlier this year with Trinidad State Junior College’s NRA Gunsmithing School regarding the normal dimensional variance between a M98 Mauser bolt face and the relating cartridge. I was informed that the normal variance for the bolt face counterbore is .004”-.006” larger than the CIP/SAAMI maximum specification for the cartridge rim diameter. Your Siamese Mauser is a variant of the M98 Mauser action so this information is applicable.

Now if the 348 Winchester brass chambers in your rifle you’d better do a chamber casting before firing it as the base of the 348 Winchester is substantially larger than the 45-70 Govt.

450 alaskan, andy

Yeah, I spoke too soon as to the fit of the 348 rim. I just measured one and see the virtually non existant difference. The extractor however will need to be reground if it will be used on the 348 case. At least thats how it appears to me. It is probably just a sloppy job of machining the bolt face.

So I am back to square one....I think I have a sloppily cut bolt face. I have seen a few other Siamese conversions and the bolt face has a lot more metal around the rim. The only way I know to rectify this is to tig weld and remachine. I don't have the equipment to do either. What now?

Andy

quote:

Originally posted by drewhenrytnt:
So I am back to square one....I think I have a sloppily cut bolt face. I have seen a few other Siamese conversions and the bolt face has a lot more metal around the rim. The only way I know to rectify this is to tig weld and remachine. I don't have the equipment to do either. What now?

Andy

Start writing checks; its time to hire it done.

Jason,

Can you do this work? If so, please send me your price and shipping information. If not, I don't need smart-ass remarks.

Andy

Find another bolt body and have it done properly.

Glenn