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pre-aklon
05-15-2005, 8:39 PM
So I picked up a lot of 8mm Mauser at the last San JOse gun show, using it yesterday to "test" my new Model 98/29 (one of the the SAMCO unissued rifles).

One of the boxes I picked up was Sellier & Bellot 8x57 JR, and this ammunition refused to feed in the rifle. Giving it a look, it was evident right from the git that the cartrdige base was much bigger than the other stuff I had, almost as if the case was supposed to be rimmed. It would barely fit four in the magazine, and like I said it wouldn't feed since the rim was too big to fit into the feed guide cut into the bolt face.

(The other stuff, with the smaller base, did right well, with the 170 gr spitzer printing about an inch high and to the left at 100 yds - which is to be expected since I shoot left handed.)

Comparing the ammunition at home, I found that while eveything else measured .468" diameter at the rim base, the S & B was .518.

Then I measured the bullets and found that the S&B 8x57JR was .318!

It would appear from this that while the JR won't fed into rifles configured for the JS bullet, the opposite - due to the smaller rim base - is true: the JS will feed into JR rifles.

Clearly, the 7.92 controversy only applies to owners of JR rifles but it is disconcerting nonetheless.

pre-aklon
05-15-2005, 8:39 PM
So I picked up a lot of 8mm Mauser at the last San JOse gun show, using it yesterday to "test" my new Model 98/29 (one of the the SAMCO unissued rifles).

One of the boxes I picked up was Sellier & Bellot 8x57 JR, and this ammunition refused to feed in the rifle. Giving it a look, it was evident right from the git that the cartrdige base was much bigger than the other stuff I had, almost as if the case was supposed to be rimmed. It would barely fit four in the magazine, and like I said it wouldn't feed since the rim was too big to fit into the feed guide cut into the bolt face.

(The other stuff, with the smaller base, did right well, with the 170 gr spitzer printing about an inch high and to the left at 100 yds - which is to be expected since I shoot left handed.)

Comparing the ammunition at home, I found that while eveything else measured .468" diameter at the rim base, the S & B was .518.

Then I measured the bullets and found that the S&B 8x57JR was .318!

It would appear from this that while the JR won't fed into rifles configured for the JS bullet, the opposite - due to the smaller rim base - is true: the JS will feed into JR rifles.

Clearly, the 7.92 controversy only applies to owners of JR rifles but it is disconcerting nonetheless.

-hanko
05-15-2005, 10:43 PM
'R' means rimmed, cartridge size is the same as the non-rimmed ('S') version. It's used on Siamese Mausers & a few others.

I'd slug the barrel as groove i.d. can vary among models from the same country, not to mention country to country.

Get Kuhnhausen's book on the Mauser, it has all you'll need.

-hanko