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They say a picture is worth a thousand words so please see the following link and you will get a better idea of my situation.

9x57 Mauser Headspacing (Factory vs. Fireformed)

The picture is Kynoch 9x57 Mauser brass (circa 1950s) unfired vs. fire-formed. As you can see there is a significant difference here. I guess i just wanted to know how that will effect reloading, case-life, accuracy, rifle concerns, etc...?

Like my previous post this is for my vintage Commercial Mauser Sporter k98. I would prefer to do as little as possible to keep this original or free of major modifications if possible.

Rifle pic 1

Rifle pic 2

It almost looks as if somebody ran a 9.3x62 reamer into your rifle.

Personally, I would form brass specifically for your chamber. There are at least three ways to do it:

1) Seating bullets to firmly engage the throat.

2) Necking up the brass to a larger caliber, then down again to form another shoulder in the right placem, and fire-forming.

3) The Cream of Wheat fire-forming method.

You may or may not be able to use the dies you have. If they can be backed out of the press until they don't push back the fire-formed shoulder, but then the cases still might not get sized enough to fit the chamber, especially after a few firings. You might need a custom die.

Some people would re-chamber, but that's a really neat rifle (!) and I'd leave it alone if at all possible.

JB gives good info (as usual) but I would recommend strongly his method #2.

Easy, effective and no high pressure concerns.

Necking up the brass as you suggest in option 2 above; do you have a caliber selection i should use as a starting-off-point for necking up?

I currently have a RCBS .358" Neck Expander die http://www.midwayusa.com/viewProduct/?productNumber=761707 would that fit the bill?

This is my largest caliber i presently have dies for so i will have to get ahold of something if needed. I would just like to be sure i am in the ballpark with my next step/purchase of equipment.

Thank you

I'd neck it up to at least .375 if you use that method, which unfortunately means obtaining something you don't have.

The other two methods will also work, if you don't want to spend the extra money.

Seating bullets well out, so that they're firmly in the lands, is probably the simplest method--but some of those older German rifles have very long throats.

I missed getting on on the other thread, about bullet diameter. Have you measured the bore yet? I have also found that older German rifles can have widely varying bores. My wife has a 9.3x72R combo gun that (luckily) actually has .35 caliber bore and groove diameters, .350 and .358, which makes it really easy to load for. Didn't find that out until after she bought it--and it came with half a box of standard 9.3x72R factory ammo that the previous owner had already fired in it!

The Cream of Wheat method does work very well too, and is the cheapest solution of all, though it does take some experimentation to get exactly the right load to fill the cases out completely.

If the bullet end of the factory 9mmx57 will slip into the muzzle end of the bore all the way down to the case mouth and still have a bit wiggle room, I would start suspecting that MD is correct in that the rifle is chambered and bored 9.3x62 and is not a 9x57. Making a Cerrosafe chamber cast might be a good idea.

No, I have not measured the bore as yet. I will try the suggesting carbon12 suggested also to verify the true 9mm vs. 9.3mm just to be safe.

Is measuring the bore something i can do for myself or it needs to go to a gunsmith?

Depending on one's skills with precision measuring tools, the difference between 9mm and 9.3mm is big enough to determine with the ID jaws of standard calipers.

No advice to offer, just wanted to comment on the rifle....WOW, that one has character!

RH

JB gave you good advice.That is really a kool rifle!!!!

I guess if you have an empty 9.3x62mm case, then you could see if it chambers. If it chambers, the next thing would be to find if the neck of the chamber is long enough to accept and safely fire loaded 9.3x62mm. If it chambers and the neck is too long on a 9.3x62mm case, then possibly it could be trimmed. Next issue could be loaded overall length, depending on the throat.

Seems it would not reliably fire 9x57mm ammunition due to excessive headspace.

grissins,

As carbon12 already suggested, using a dial caliper to measure the bore at the muzzle is good enough to tell if it's 9mm (.356) or 9.3mm (.366). Try to measure between the grooves on either side of the muzzle.

The precise way to measure a rifle bore is to push a slightly oversize "slug" of soft lead through it, then measure that. That isn't necessary to tell the difference between 9mm and 9.3mm, but if the bore is around 9mm, then it would useful information for the bullets you finally use.

WOW! Now this is an extreme example of fireforming!

Thank you, i really like the look and feel of it myself. Even the scope a Gerald C model scope has some interesting features on it i seem to still be learning about.

http://www.runcss.com/MAI/pix365163726.jpg

What made you believe that the rifle is a 9x57 in the first place? Is it stamped with that somewhere?

The barrel is stamped <see pic>
However to me that seems that it might be post-production stamping? Do you think it could be?

http://www.runcss.com/MAI/DSC01171.JPG

I do know it will fire the 9x57 well though it sure does inflate the shoulders on the factory Kynoch ammo in my initial post.

The 'inflation' of the case you see is your rifle telling you not to fire it again with 9x57 ammo. Someone, at a minimum, has run a different chambering reamer through it and did not remark it.

Unless you got really lucky and the bullet nose was jammed against the rifling, there was some excess headspace going on (DANGER). The firing pin was able to strike the primer because the case was held back by the Mauser CRF extractor.

Unless you are a fast learner, you may be in over your head with this rifle. Best get it to a Pro for a check up.

If it turns out that your rifle is a 9.3x62, you will be all set. Factory ammo and everything for reloading can be ordered from almost every shooting supply house.

Radical case forming isn't unknown in old firearms that existed prior to standardisation and where manufacturers had their own thoughts on what was ideal. The 10.75x68 can be like that, so can the 450/400NE and 500Jeffery. If a 9.3x62 reamer was run in during modern times and whilst the firearm was still in Europe, it most likely (depends on the country) would have needed to have been re-certified for proofing purposes ... there's no proof marks under the stock line somewhere? A 9.3 reamer into a barrel that nominally ran somewhere between 0.355" and 0,358" is kind of interesting too.

This rifle is a wonderful mystery ... I'd be inclined to pass it to a gunsmith for a chamber cast. Armed with that information, you could proceed with some confidence. Whose to say for instance that its not a 9.3x57 reamer that's been applied (perhaps a fraction too deeply to get a clean cut) ... and the pressure differences between the two (x57 and x62) are worth respecting. The 9x57 for example is a 2800bar chambering whilst the 9.3x62 is a 3900bar chambering.

Worth proceeding cautiously and having a chamber and throat cast made. The bore size too is important ... there's a gunsmith in Australia that still has his hydraulic press and drawdown dies from the 1970-80s when doubles of nominally 0.458" where being found to have anything from 0.460" to 0.451" bores, so he was customizing Hornady 500gr projectiles to suit the bores of the rifles. He was even drawing them down as far as 0.440" to get a few 11.2 Schuler's running.
Cheers...
Con

Looks like P O Ackleys long lost twin has finally been found... .

Seriously though...curious how it wound up that way. Too bad that your rifle can't talk. Nice rifle, by the way.

Cartridges of the World by Frank C. Barnes lists the 9x57mm and a 9x63mm, which seems similar to .35 Whelen. Although some cartridge dimensions are given in a table, the base to shoulder length does not seem to be given. Getting a sample of brass case or ammunition to measure seems difficult.

Finding that the shoulder location on a 9x63mm is similar to 9.3x62mm or .35 Whelen would not be surprising, but I do not know that they are similar.

I do not have reloading software to look for cartridge dimensions. The RCBS software, for example, may have enough data to show case dimensions for cartridges that would be unusual in USA.

A quick look at Stars and Stripes custom ammunition shows these 9mm rifle rounds:
Stars and Stripes Ammunition (727) 530-1129 www.starsandstripesammo.com
Page 5 of 7 Obsolete Metric/Euro Cartridge List Last Revised January 1, 2008
9X56mm Mannlicher-Schoenauer
9X57mm Mauser
9X57Rmm Mauser
9X63mm
9X70Rmm Mauser 400/360 Westley Richards Nitro Express
9X71mm Peterlongo

If you can figure out what you have, then ammunition could be available from them, or other custom makers.