With a 24" barrel 2800 might be a little optimistic. I would think more like 2600-2700.

I have seen and handled a nice custom rifle in 9.3x64 on a factory modified H&H style P-64 and this is the best way to go, IMO. But, in the hands of a good 'smith, a .30-06 action will work although getting four down is problematic.

What I would do is to use a Wisner, Sunny Hill or Blackburn drop mag box for the "short mags" and have a GOOD smith fit this and alter the bolt face and feed rails for the Brenneke cartridge. Then, cut the bolt stop back (about .125") and fit a "Classic" extractor ring with the improved gas block and, if done properly, you will have a superb, 5 shot rifle in the finest medium bore cartridge ever invented.

You can push your 250 bullets to 2700 and a bit, in your 24" bbl, but, the 286 gr. Nosler PT. in this does an easy 2600 and kicks less than a .375 H&H (to me); it also shoots flat enough to at least 300 yds. for any rational use.

Unless I am badly mistaken, the pre-64 M70 was always built on a .375 length action. Shorter cartridges, some as short as the .218 Bee, were just blocked in the magazine. Therefore, there should be no problem at all with your rechambering. Only the magazine capacity is questionable.

The best I have ever gotten in a 9.3x64 is 2701 FPS, 10 shot average with a 26 inch barrel with 77 grs. of H414...

I got 2800 to 2850 with 250 gr. bullets.

I got 2485 FPS average with a 320 gr. Woodleigh and 65 grs. of 4895, and thats a real hammer of a load..

I found the best powders to be IMR-4320, H414, 4895, and IMR-4350...

Based on these and other loads that I chronographed, I settled on the 9.3x62 with a 26" tube, as I can come close enough to the 9.3x64 for all practical hunting, and have room for an extra round in the magazine and get a bit less recoil. Thats not saying the 9.3x64 is inferior, it stating that I just did that, nothing more...

In fact the 9.3x64 is probably the most perfect all around caliber in the world, beating out the old 375 H&H, and the great 338 win. But the 9.3x64 brass situation has about voided it in the USA, now we have Horneber but for how long is my question and RWS is hard to come by...so I opt for the 375 H&H...

All "old" Mod. 70 receivers were exactly the same size, actually a bit too short for H&H length rounds. That is why I refered to "factory modified"; the 9.3x64 I am most familiar with is on an FN c-ring, commercial action made for Husqvarna, originally in 8mmjs. This would be my first choice for a 9.3 and, with the mag. box I mentioned, and some very minor mods by Martini&Hagn, it will hold five plus one and feeds like silk....but, he won't trade it to me!!!

I agree with "Atkinson" on both his opinion of the Brenneke round and his choice of the 62mm cartridge for daily use. If, Winchester would produce brass for the 64mm round, I would have one forthwith.

I had an equally hard time finding 8x68s brass while doing research on it with the consideration of starting a build up of one this spring.

Z1r was kind enough to share this with me: Huntington's RWS. Down at the bottom is some 9.3x64. Expensive, but its there.

Jason

Thanks to all for the info. so far! I understand that all pre - 64 are the same length, Although the 375 and 300 H&H actions where opened up and they also received a different heat treat. I should have inquired further with the 30 - 06 mag. box functioning for the 9.3 x 64 cartridge. I first considered the 338 win for this project, but smith prefers the newer Mdl. 70 which is slightly longer for the 338 round, which I agree with and I have a very nice pre -64 on hand that is teasing me to do something with it.

Many Thanks
HBH

I would build a .35 Whelen on it, it just seems to fit the American action somehow. I recently sold a gorgeous H&H style P-64 action and also a minty .30-06 one; now, I wish that I had built up a .35W. It has taken me several years to recover from "old Model 70 syndrome"...........

Of course, I still have a "few" left!