New wildcat: 9.3mmx.338 Win. Magnum

[Advocate]

Although the .338 Win Mag case has been necked up and down (i.e. .264 Win Mag, 7mm Rem Mag, .30-338, 8mm-338, 358-338, 375-338, .458 Win Mag) I have never heard of it, or any of the other belted mag cases, necked to 9.3 mm (i.e. .366). This is a rare bore in American, although it is more widely used in Europe and Africa, as a result of the old, classical medium bores in the form of the 9.3x57, 9.3x62, 9.3x64, and 9.3x74.  

There are some really juicy 9.3 bullets made by Speer (270 grain semi spitzer), Nosler (250 Grain BT, 286 gr Partition), Woodleigh (250, 310 grainers), Swift A Frames (250, 285, 300 grain A Frame bullets) Hawk bullets (200, 235, 250, 300) and Barnes (250, 285 X bullets).

I think a 9.3-338 Win Mag would be kind of neat.  Any body else have any thoughts?l

[Joe Kool]

I was just reading about the 375-338 in an old Handloader #154 Nov.- Dec. 91. The 9.3 bore is only .009" smaller then the .375", so you could use the 375-338 loading data in the article as a guide line for the 9.3mm-338. After reading the article I was wondering why a 358-338 or an 8mm-338  never became popular. They will fit in standard length actions. They could all be build on 98 Muaser actions.  

[Advocate]

Joe:  You raise interesting points about the .358 and 8mm chamberings on the .338 belted magnum case and their lack of popularity.  First, medium bores are not the most popular calibers in any event.  Second, neither the .35 nor the 8mm have done very well in the USA in recent decades.  One reason was the lack of premium bullets (Nosler partitions, etc.) until very recently. Don't forget that the 8mm Rem Mag  and  the .350 Remington Magnums flopped too.  The .350 Is making a come back, allegedly, but only time will tell.  The .35 Whelen is moderately popular.  The .358 Norma factory round is ballistically identical to the .358-.338 wildcat.

Interestingly, Speer offered reloading data on the 8mjm-.338 mag some years ago, calling it the "PMM",  poor man's magnum.  The ballistics were very uninspiring and considering that most bullets were designed for the more modest 8mm Mauser velocities, it is easy to understand why this combination did not really catch on.

[Joe Kool]

Advocate, if you had a 98 Mauser in 8mm Mauser, rather then chamber it to 8mm/06, it could be chambered to 8mm-338. The bolt face would need to be opened up, and the magazine follower would need to be altered for the belted case. Most gunsmiths can do this. You would have cartridge more powerfull then the 8mm/06. The velocity would be real close to the 8mm Rem. mag.. Several bullet makers carry bullets for 8mm Rem mag. velocities, so bullets are no problem. There are some calibers that are just not popular with American hunters, and it's a real shame that they are missing out on these wonderfull performers. I've used the 6.5x55 and the 260 Rem. and they are great performers on deer. The 358 Win., the 35 Whelen and the 350 Rem. mag. are all super calibers that never caught on. The 375 Win. is a great cartridge, for the short range brush hunting here in the east, that most hunters don't even know exists. I've seen the 8mm mauser use very effectively on deer, and how most people hunt, it's all the power they need. The 8mm Rem. mag is a screamer that never caught on. Once seen a hunter shoot a deer shoot a deer at about 250 yds. with one, I was impressed.  I've seen hunters using 7mm and 300 Win. mags hunting in the bush where you would be lucky to get a 100 yd. shot. The 375 Win., 358 Win. or a 35 Rem. would be far better cartridges to use. Today almost everybody is magnum crazy, the faster the better, even if you don't need it. They turn their noses up at a 9.3mm x 62 or a 356 Win.. Right now I'm building a 35 caliber wildcat on a 375 Win. case for a contender carbine. The bullet I'm going to use is the Lyman #358318, about 250 gr. cast of wheel weights and 2% tin. I estimate the velocity will be 1800- 1900 fps. Doesn't sound like much, but a 250 gr. bullet at 1850 should be a real thumper out to 200 yds.