Other than the obvious rifle type the cartridges were designed for, how close are these two? 400grs at 2100fps. The .411 bullet has a little better SD, the Mauser has magazine capacity. Anyone with field experience with either of these rounds? A lot of hoopla recently about the .450/400 thanks to Ruger and Hornady.

Well, just reading the data about the two weapons, they are still remarkably different. Thirty years ago I owned a 10.75x68mm Mannlicher-Schoenauer which I sold off because I could not find ammunition. Today, If I had to have a weapon in that power class I would opt for a .450-400 double, as it just shoots faster, and it would of course be a DGR weapon. Sadly, my arthritis has terminated my enjoyment of heavy caliber rifles. However, now that ammunition is once again available, I would say go for the .450-400. I would trust to Ruger and Hornaday before I trusted RWS-RUAG for my ammo.
LLS

You using Ray Atkinson's loads in that 10.75x68mm Mauser?

10.75x68 factory/CIP loads would be more like:
347-grain (CIP 10.78mm = 0.4244" caliber)~~.423/.424 bullet at 2200 fps (Eley-Kynoch) or 2230 fps (RWS), for 3740 to 3830 FP-KE. 59.0 grains of IMR-3031 is supposed to give 2250fps/3900KE.
CIP max.ave.pressure is supposed to be 3300bar or 47,850 psi.
Surely 2100 fps with a 400-grainer would be no problem, from a similar barrel length, and will probably be in CIP pressure spec.

The 450/400 NE 3" or 400 Jeffery NE:
400gr bullet of smaller diameter (CIP 10.41mm = .4098" caliber) ~.410, but greater sectional density
2100 fps 3920KE
2800bar or 40,600 psi.

AcculoadIII says the gross water capacity of the 10.75x68 is 94.8 grains of water??? Verification from an owner would be appreciated.

I can measure the Hornady 450/400NE3" water capacity later.

The water capacity of full length 400/395NE-Righteous-One brass from Quality Cartridge is yet to be determined, but it will be close to 90 grains gross. Going from 2.900" to 3.000" in Hornady basic ads 3.09 grains of water capacity, 88.6 + 3.1 = 91.7 grains gross.

Yep, the "Righteous One" will beat all the antiques, and "400 Pretenders" with less recoil, and even better sectional density for given weight of bullet. Slightly higher pressures in modern single shot or double will be no problemo.

One curious CIP fact is that the 10.75x68mm uses a 10.78mm bullet (.424"), and 1:16.5" TWIST.

The .404 Jeffery (.404 Rimless NE) uses a 10.72mm bullet (.422"), and 1:16.5" TWIST.

So the standard used in both has become .423"?

450/400NE3": 1:15" TWIST according to CIP.

The .404 Jeffery max.ave.pressure is 3650bar = 52,925 psi. CIP Modernized since 1905, no doubt.

When will CIP recognize the 400/395 Righteous Nitro Express?

RIP, I measured the water capacity of an unfired Bertram 10.75x68 case using our clinic micro scale. I get 92.59 gr. Does this sound right?

Helped pick up the squashed remains of a local citazen hunter who tried to use a 10,75 on ele. Fatal mistake. The SD is too poor. Great lion rifle and adequate for buffalo. Most Mauser 10.75s we see have been converted to .404- but it is not always a great conversion because the 10.75 usues a marginally fatter bullet (as Rip states) and with a worn barrel...you get a rattling good fit with .423" bullets.

Have re-cut the rifling to .427" and reamed the chamber out to use a shortened .404 case (with shoulder blown forward etc. Shoots 425grn solids at 2300fps or any .44 mag bullets.

It was an interesting experiment and has kept a well worn Model A Mauser in use!

Ganyana, Was the poor chump using factory 347gr ammo? Historically, this load has been a poor performer. We will be loading 400gr Woodleighs at 2100FPS and still keeping the pressure below 50K psi. This more modern load whould be comparable with the .450/400. The SD of the .411 Woodleigh is .338 vs .319 for the .423. Will this difference make the 10.75 a non-player? Thanks for the reply

Wasn't it Harry Manners who started ele hunting with a 10.75x68 but soon realized that it was inadequate (with 347gr factory/traditional loads)?

VFR a 400grn bullet at 2100 is still marginal on a big bull ele IMHO. Several PH's are re-discovering why the .470 wasn't the best of the double rounds - penetration of Federal factory is barely adequate - good enough for a client but not for a PH trying to take poor angle back up shots.

Brian Marsh switched to a 450 Watts in the late 1960's finding it alot better than a .470 and more recently, Mike Payne has mae a plan to aquire a .416 to replace his .470 on ele.

Similarly the .404 never achieved the reputation of the .416 rigby because of a combination of poor bullets and only just adequate penetration. RWS with modern loads did alot to improve the .404 and it was this ammo that was so popular here with culling officers. a 400grn .423 bullet at 2300fps was all that anyone needed.

Rule of thumb for elephant. For an SD of 305 you need 2300fps. For an SD of 3.40 you need 2050fps

Buffalo? A good bullet will make the 10,75 more than adequate in any loading.

Ganyana, Will never hunt ele, but buff is a definite. I have a Win M70 .458 but had much rather go with something more traditional. My 10.75 is a type A Mauser copy complete with raised side panels, pancake cheek piece and intrical front and rear islands and sling swivel. Actually at the stock maker as we speak. The 9.3x64 worked great in Namibia for plains game, but just want to take the 10.75 for buff and a zebra.

integral

Thanks Will, I'll look for the spell checker next time, was in a hurry.

I have built a couple of 10.75 x 68s and in fact sold them on AR...I have also shot a few head of plainsgame including Eland and a few buffalo with it.

I found that they duplicate the original loadings of the 404 Jefferys and the 450-400s with the 400 gr. bullet at 2100 FPS pretty easy and thats fine for Buffalo, Lion and plainsgame up close..but the best load for the 10,75 x 68 is a 350 gr. Barnes X at 2375 FPS, now that is a killing machine, but still not what I would choose for elephant unless thats all I had at the time...

The nice thing about the 10.75 is it will hold a lot of ammo, depending on the box you use but figure on 4 down and 1 up with a std. Mauser box. and it makes up into a nice, light rifle thats very easy to pack around all day...

I guess I would say it is a better option than the 9.3x62 on Buffalo and Lion and thats no slight praise as th e 9.3 is one of my all time favorite calibers..Used on this stuff the 10.75 is quite a neat cartridge when properly handloaded..

The downside might be if Horneber ever quits making brass for it, so if I had one then I would purchase about 500 pieces of brass.

I think its as good a cartridge as the 450-400 which will push a 400 gr. bullet at 2150 FPS or a little better in a Searcy rifle...If not its got to be very close indeed.

One thing that I am sure of and that is the 10.75 is a most underrated and misunderstood cartridge.

I would never use the 347 gr. bullets with it, but the 350 gr. monolithic is longer and like all monolithics you can get away with lighter bullets whereas a bullet of like weight in a conventional bullet you cannot....

Thanks Ray, This is the answer I was looking for. Do you have a decent load for the 350gr Barnes? VZ 24 action with a Danny Pedersen bbl.
The box and floor plate are FN with bow release.

PS: Ray, who has the 350gr Barnes X in 10.75?
Thanks

By Ganyana!
"Rule of thumb for elephant. For an SD of 305 you need 2300fps. For an SD of 3.40 you need 2050fps."

That is why the 550 grain .458 diameter
Woodleigh with a sd of .375 is so outstanding for both penetration and thump power when loaded to 2,150 fps. out of a Lott.

465H&H

Here´s my Mauser M98A in 10,75 Mauser.


At the time, I´m reloading 63grs R902 behind a 350grs strong jacked protected point bullet made by Degol.
Sorry, I have no hunting experience with this round. I´m only gunsmith, no hunter.
A friend shoot cape buff´s with this round and FMJ at his time as professional. He means, with good placed shoots, it´s a good killer.

Martin

VFR1,
Well the 350 gr. Barnes Xs are a problem, they discontinued them, but contace GS Customs and they can take care of you on that order......

The loads I used with 350 gr. bullets are:
Fed. 210 Primers
Horneber brass
64 grs. of H335 foam filler (DACRON 3 to 5 grs.)
56 grs. of H4198
66 grs. of VV140
61 grs. of Varget

All max loads in my gun so cut back at least 10% and go from there...There can be big differences in those old European chambers as I think they just ran a reamer in them and stopped when they decided it had gone in far enough!!

400 gr. woodleighs:

210 Fed primers
Horneber brass
74 grs. of WW748
55 grs. of IMR-4198

Hope this helps you out..One thing for sure and that is the 10.75x68 is a fun caliber to play with and much overlooked dangerous game round. If properly loaded it is as good as the 450-400 or the origingal specs of the 404 that made the .404 famous and with todays good bullets its a fine caliber, and has a lot going for it in that its light and easy to pack, holds more ammo than most, and its a good killer.

Thanks Ray. I've got plenty of H335 and 748. Looking forward to trying the Hornady 400's when they become available.

quote:

VFR a 400grn bullet at 2100 is still marginal on a big bull ele IMHO. Several PH's are re-discovering why the .470 wasn't the best of the double rounds - penetration of Federal factory is barely adequate - good enough for a client but not for a PH trying to take poor angle back up shots.

Brian Marsh switched to a 450 Watts in the late 1960's finding it alot better than a .470 and more recently, Mike Payne has mae a plan to aquire a .416 to replace his .470 on ele.

Ganyana,

I am always preaching penetration index but few pay any attention!

I think an alternative to the 470 NE factory load's penetration doubt is the use of the flat nose solids that are/were available. They do have great penetration, in my limited experience anyway. I am now a true believer. I think they should eliminate the 470's potential lack of penetration.

Penetration was what made the Rigby's reputation. A good flat nose solid would even make it better. So I wouldn't necessarily give up on the 470/458/etc.

Interesting!

I can think of three Zim PHs that are 416 Rigby users that are looking for a 470 or 500 double. They want more stopping power than any of the 416s deliver.

465H&H

The classic conundrum. Do you want penetration or power (knockdown)?

To have both it is going to take a lot more than anything I care to shoulder! Pick your poison and hopes it works.

I have never found the .470 lacking in penetration on anything, but I also use the right bullets, my favorite being the Flat nose Bridger customs or GS Customs..but I sold my 470 to buy another 450-400 and I have no compliants with it on anything again with proper bullets, but good bullets are a must IMO with ANY caliber...

My all time favorite double was a 450-400 necked down to take .416 bullets and it was awesome, but I sold it and strangely enough I still have those dies, have no clue what I will ever do with them!

/

quote:

Originally posted by ALF:
The historical lack of sufficient penetration by the 470 lay solely at the foot of the geometry of the solid bullet in which it was originally loaded.

The typical shape of the typical bullet puts the centre of gravity way behind the geometrical midpoint and when combined with it's particular tranverse moment of inertia it becomes a poor penetrator because of early in target instability. Taylor observed this, wrote about it, but did not seem to understand why, nor did many others.

John Buhmiller understood the instability theorem and he was, as far as we can see the first person who in the field of hunting bullets experimented with the manipulation of geometry to increase penetration by negating in target instability.

What is of interest is that those who designed military bullets for the British 303 manipulated geometry of FMJ's to induce instability.... what they did not do and one cannot quite understand why they did not apply the same principles to get the opposite effect in hunting bullets.

Right on, Alf. But even in a straight line it was nothing to write home about.

quote:

Originally posted by ALF:
The historical lack of sufficient penetration by the 470 lay solely at the foot of the geometry of the solid bullet in which it was originally loaded.

The typical shape of the typical bullet puts the centre of gravity way behind the geometrical midpoint and when combined with it's particular tranverse moment of inertia it becomes a poor penetrator because of early in target instability. Taylor observed this, wrote about it, but did not seem to understand why, nor did many others.

John Buhmiller understood the instability theorem and he was, as far as we can see the first person who in the field of hunting bullets experimented with the manipulation of geometry to increase penetration by negating in target instability.

What is of interest is that those who designed military bullets for the British 303 manipulated geometry of FMJ's to induce instability.... what they did not do and one cannot quite understand why they did not apply the same principles to get the opposite effect in hunting bullets.

Alf, I know the theory behind the 303 bullet having sectioned several but how would you go about reversing that principle in a hunting bullet? Short of having a true cylinder with its attendant problems with feeding a BC like a well,.... true cylinder would a solid with a hollow tail go some way to address this? I'd pick that you might run into hassles with projectile length then, especially in monos with their lower density & greater length for weight.
Steve.

When thinking of 10,75x68 only the phrase: "BUY THE RIFLE NOT THE ROUND" comes to mind. Some all original vintage Oberndorf Sporters make wonderful wall ornaments.