…Especially since I already have a 9.3x62.
I first learned about this cartridge in Pondoro Taylors African Rifles & Cartridges many years ago, and I’ve had a bit of a fascination with it ever since, though I’m hard pressed to say exactly why.
This should have been a much more popular cartridge, but it’s had a few things going against it right from the start. The first problem is that light for calibre bullet. The original loading was a 225 gr. semi-spitzer or solid at an advertised 2660 fps. It would have been much better, I think, to have used the 310 gr. bullet from the original .400/.350 and just increased the velocity to 2,350 or so. The other problem was that it was kept as a proprietary cartridge, and the only place to get rifles or ammo was from Rigby’s. The final nail in the coffin came in the late ‘50’s when Kenya instituted minimum calibre laws, and .350 wasn’t it. Shortly after that Kynoch abdicated their responsibility to thousands of hunters and ceased manufacture of centrefire rifle ammunition. So the cartridge went from being not too common, to downright scarce. Many Rigby .350 Mausers were re-bored and re-chambered to .375 H&H.
In appearance, the .350 looks for all the world like a miniature .416 Rigby, though the reverse is actually true. The .416 is really an enlarged .350, coming out four years after the .350. It was always somewhat underloaded as many British cartridges of the period were. Performance has been compared to that of the .35 Whelen, a much smaller case. But when you look at that long, lean cartridge, it just seems to have so much potential. And that .35 calibre bullet just looks right.
Cases can be made by laboriously turning the belts off of .375 H&H brass, running them through a sizing die and trimming to length. Most ( not all) original .350 Rigby’s were built on magnum Mauser actions. A standard action would work if it was opened up internally as it is for the .375 & .300 magnums. If loaded to the same pressures as any other modern cartridge, performance should rival or exceed that of the .358 Norma Magnum. Load data is as scarce as the rifles, probably because the owners of the original rifles lock them away in vaults rather than take them hunting.
I picked up a set of dies at a gun show a few years ago, just on a whim, and a made up a couple of cases just on an experimental basis. But original Rigby rifles are just completely out or reach financially. So the only options for owning one are to get an existing rifle re-barreled, or start a custom project.
My 9.3mm is nearing completion, my 7x57 had better be complete this year, and the last thing I want is to start another custom project. It would mean finding a donor Mauser, getting a barrel, having it turned and chambered (plus I’d have to buy my smith a reamer), get the sights fitted, figure out what I’m going to do about a scope, get a new magazine box, get the internal alterations sorted out, find a nice piece of lumber and get it carved into a gunstock, cajole my gunsmith into taking on the project and hope I live long enough to see it completed.
It would be easier and cheaper to just stick to the 9.3mm or get a pre-64 M70 in .338, and use all the money I’d save to actually go hunting.
BUT I STILL WANT A .350 RIGBY!!!
Left, a .338 Winchester Mag, centre the .350 Rigby, right, 9.3x62
Experiments in case forming; centre one was chucked into a drill press and the belt removed with a fine tooth file. Right one was much more neatly done in my case trimmer. A miniature lathe would be ideal, just don't happen to have one.
I first learned about this cartridge in Pondoro Taylors African Rifles & Cartridges many years ago, and I’ve had a bit of a fascination with it ever since, though I’m hard pressed to say exactly why.
This should have been a much more popular cartridge, but it’s had a few things going against it right from the start. The first problem is that light for calibre bullet. The original loading was a 225 gr. semi-spitzer or solid at an advertised 2660 fps. It would have been much better, I think, to have used the 310 gr. bullet from the original .400/.350 and just increased the velocity to 2,350 or so. The other problem was that it was kept as a proprietary cartridge, and the only place to get rifles or ammo was from Rigby’s. The final nail in the coffin came in the late ‘50’s when Kenya instituted minimum calibre laws, and .350 wasn’t it. Shortly after that Kynoch abdicated their responsibility to thousands of hunters and ceased manufacture of centrefire rifle ammunition. So the cartridge went from being not too common, to downright scarce. Many Rigby .350 Mausers were re-bored and re-chambered to .375 H&H.
In appearance, the .350 looks for all the world like a miniature .416 Rigby, though the reverse is actually true. The .416 is really an enlarged .350, coming out four years after the .350. It was always somewhat underloaded as many British cartridges of the period were. Performance has been compared to that of the .35 Whelen, a much smaller case. But when you look at that long, lean cartridge, it just seems to have so much potential. And that .35 calibre bullet just looks right.
Cases can be made by laboriously turning the belts off of .375 H&H brass, running them through a sizing die and trimming to length. Most ( not all) original .350 Rigby’s were built on magnum Mauser actions. A standard action would work if it was opened up internally as it is for the .375 & .300 magnums. If loaded to the same pressures as any other modern cartridge, performance should rival or exceed that of the .358 Norma Magnum. Load data is as scarce as the rifles, probably because the owners of the original rifles lock them away in vaults rather than take them hunting.
I picked up a set of dies at a gun show a few years ago, just on a whim, and a made up a couple of cases just on an experimental basis. But original Rigby rifles are just completely out or reach financially. So the only options for owning one are to get an existing rifle re-barreled, or start a custom project.
My 9.3mm is nearing completion, my 7x57 had better be complete this year, and the last thing I want is to start another custom project. It would mean finding a donor Mauser, getting a barrel, having it turned and chambered (plus I’d have to buy my smith a reamer), get the sights fitted, figure out what I’m going to do about a scope, get a new magazine box, get the internal alterations sorted out, find a nice piece of lumber and get it carved into a gunstock, cajole my gunsmith into taking on the project and hope I live long enough to see it completed.
It would be easier and cheaper to just stick to the 9.3mm or get a pre-64 M70 in .338, and use all the money I’d save to actually go hunting.
BUT I STILL WANT A .350 RIGBY!!!

Left, a .338 Winchester Mag, centre the .350 Rigby, right, 9.3x62

Experiments in case forming; centre one was chucked into a drill press and the belt removed with a fine tooth file. Right one was much more neatly done in my case trimmer. A miniature lathe would be ideal, just don't happen to have one.
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