Anyone loading for the 8x51K? I noticed in Jon Speed's Mauser book that Mauser listed the chamber pressure for this cartridge at only 41K PSI for a 157gr bullet at 2100 fps. Since the Kurz action was also chambered for the .250-3000 listed by Mauser at 50K PSI, it seems reasonable that the 8x51K could be hand loaded for improved performance. Would be interested in a any experiences with this old and obsolete cartridge. Reason for post is not purely academic. Am considering a rifle chambered for the 8x51K.

Many thanks,

Roger

Many years ago (40 odd years) I did load up some cartridges for the elderly owner of a nice little Mauser K in 8x51 complete with Kahles scope. I don't know the details of the owner in so far as to how he came to have the rifle without ammo, maybe he just ran out but didn't even have any empty cases, although he did have a reloading die set for it. He may have only just got the die set, I was working through a third party so didn't get any other info.

I had a copy of Cartridges of The World so was able to get some details on the 8x51 cartridge from that. I just ran some 308 Win cases through the FL die, obtained some .318" 8mm bullets, the weight escapes me now, as does the load and powder but I was using a lot of 4064, 4895 and 4320 powder back then for various cartridges I loaded for. Likely just used a starter load for the 308 Win. Got an accurate load worked up in the 308W cases which worked perfectly.

I used a permanent red pen to colour the primers and heads of the loaded 308W cases and glued a warning note on each packet of cartridges to the effect that they were 8x51 cartridges and must not be fired in a 308W rifle.

Heard the owner got a few deer with the Mauser 8x51 and new cartridges but never heard what became of the rifle.

Sorry I can't help with details on the load I developed, I did have it on hard file for years but culled a lot of data when I converted over to electronic.

Eagle 27,
Thank you for replying to my post. I knew the 8x51K was obsolete but I guess it's right & truly dead. I've just purchased a Kurz sporter in 8x51, and while it's sacrilege to tear down an Oberndorf rifle, the action is too good to just sit and gather dust. A new barrel is in order but I haven't decided on the new cartridge yet.

Never built one but it would be easy to do; (dies will be the hard part).
I'm sure that an 8mm would not chamber in a 308 so I would not worry about that.
It was a good cartridge, as were all Mauser inventions; (the 8x57 was not one of them, contrary to popular belief).
Go for it. And load to 50K psi.

If you do decide to rebarrel, that Kurz action would be wonderful in 250/3000. Just like originally intended...

quote:

Originally posted by RogersGunWorks:
Anyone loading for the 8x51K? I noticed in Jon Speed's Mauser book that Mauser listed the chamber pressure for this cartridge at only 41K PSI for a 157gr bullet at 2100 fps.

Forty one thousand psia not enough for you? You need more, because more means more?

I am of the opinion that before exceeding the manufacturer's load pressures, you need to understand why it was set for 41 Kpsia.

Was it set because older rifles were made out of poorer materials?

Or was it because the rifles in 8 X 51K were not made for extended use at pressures above 41 kpsia?

My opinion, if you have a rare and valuable action, it is your to chamber to any cartridge you want. But if you crack lugs, or seat back the receiver seats, with over pressure loads, was the extra velocity worth it?