Has anyone out there heard of a round called either the 366 Alaskan or 9.3 x 338? Seems to me it would be a fun caliber to take into the field with a 286 gr bullet in front. Chuck Hawks lists it in his wildcat section, the pay section of course, but if anyone knows where I can find some other load data it would be much appreciated.
9.3 x 338 Magnum
- Thread starter fltengalan
- Start date
I have a 9.3 x 64mm Brenneke, and that's actually how I make my brass! The .338 Winchester is basically the 9.3 Brenneke necked down to .338 with a belt added. So it just goes to show that there's not much that can be invented that hasn't been already. I'll see how much load data I have and send it in a PM. In either iteration (belted or otherwise), it'll pack a nice wallop for pretty much anything.
Northman999
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I too toyed with the idea of a 9.3x338 win mag.
Sounds like a very good cartridge, but I already own .338 win mag, 9.3x62 and .375 mag, so I decided I didn't need to put money into a custom.
cfbmi's 9.3x300 win mag is going to hold about 6 grains more powder than the .338 version. If I was building a custom, I'd go with the .300 version over the .338 version; no reason not to grab that extra 6 grains of powder, and the brass is at least as common.
Also, companies like Trade ex carry 300 grain .338 hunting bullets fairly regularly now, so standard 9.3 bullet weights really don't add much to that.
A "normal" 338 win mag will push 300 grains @ 2500 fps so that's fairly respectable.
Actually, if a guy chronied a bunch of factory .375 H&H ammo, he'd find that 300 @ 2500 was not very far (...at all...) from factory .375 H&H. Winchester's factory .375 H&H in Nosler Partition and Nosler Solid are rated at 2530 fps, for example. And that's factory ratings, actual chrony readings may very well be less.
Still, 9.3x.338 is a very reasonable wildcat for things like moose, grizzly and Bison, I'm sure.
Sounds like a very good cartridge, but I already own .338 win mag, 9.3x62 and .375 mag, so I decided I didn't need to put money into a custom.
cfbmi's 9.3x300 win mag is going to hold about 6 grains more powder than the .338 version. If I was building a custom, I'd go with the .300 version over the .338 version; no reason not to grab that extra 6 grains of powder, and the brass is at least as common.
Also, companies like Trade ex carry 300 grain .338 hunting bullets fairly regularly now, so standard 9.3 bullet weights really don't add much to that.
A "normal" 338 win mag will push 300 grains @ 2500 fps so that's fairly respectable.
Actually, if a guy chronied a bunch of factory .375 H&H ammo, he'd find that 300 @ 2500 was not very far (...at all...) from factory .375 H&H. Winchester's factory .375 H&H in Nosler Partition and Nosler Solid are rated at 2530 fps, for example. And that's factory ratings, actual chrony readings may very well be less.
Still, 9.3x.338 is a very reasonable wildcat for things like moose, grizzly and Bison, I'm sure.
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A friend of mine toys with a 9.3X338 Lapua. That smacks.
Personally, instead of spending money on custom dies and chambering, and time developping loads with a 9.3X338, I rather use one .358 Norma Magnum (which I already do). There are bullets up to 300 grains, maybe more, readily available..
Personally, instead of spending money on custom dies and chambering, and time developping loads with a 9.3X338, I rather use one .358 Norma Magnum (which I already do). There are bullets up to 300 grains, maybe more, readily available..
Just went and compared the case dimensions of the 338, 9.3 x 62 and 9.3 x 64, and the difference seems to be that both the 338 and 62 would fit in a standard length action of 2.5 inches whereas the 64 at 2.8 inches would need a longer action. Seems to me then that though the 9.3 x 338 and 9.3 x 64 ballistics would be very close, the 338 based one could be used in the shorter action, if that matters! I was just thinking I could re-barrel my 338 to 9.3 and have a very interesting rifle to play with, but looking again at all the external ballistics made me realize that the gain in performance would be pretty minor when you start to consider the cost. Maybe a project for another day!
I highly recommend the 9.3X300 WM if you have nothing better to do with your time or money. I wildcat for the sake of wildcatting and to expand my knowledge, with more than 100 rifles I don't have any gaps in my line up, I just do it 'cause I want to. I've had to put my final ballistics testing on hold with the 9.3X300 because I'm moving right now, but so far I have achieved 2968 fps with 286 gn Parts and 3030 fps with 270 Speers. (26"tube) I have more test loads made up with 270 gn Matrix to try, but now I don't have a range at ready access.
It is a far superior cartridge to a 338 or 358 NM and exceeds what my 375 H&H will do by quite a margin (approaching 200 fps with 270s). I did not build this rifle or dream up this cartridge, a very good friend of mine did and I bought it from him and continued the load development from his data. I had designed a virtually identical cartridge based on the 8X68 case many years ago but never got around to building it. After using this cartridge, which has identical case capacity, I see no need to continue with the project.
After much chatter on the thread this spring and last fall I managed to get it out to do some external ballistics testing on a black bear this spring, it was devastating however the 270 gn Speer was not designed for over 3000 fps so bullet performance was dismal but still managed to kill the largest black bear I've ever taken.
This cartridge would kill every animal on the planet with appropriate bullets and not be undergunned for any save maybe elephant, maybe !! I would still use it though with a 300 gn solid @ 2400 fps I have no reason to believe it wouldn't work flawlessly. All other animals would be easily overcome with this cartridge. As versatile as the 375 H&H, shoots flatter and hits harder with bullets of equal weight with better sectional densities and in any action that holds a 300 WM, what's not to love.
It is a far superior cartridge to a 338 or 358 NM and exceeds what my 375 H&H will do by quite a margin (approaching 200 fps with 270s). I did not build this rifle or dream up this cartridge, a very good friend of mine did and I bought it from him and continued the load development from his data. I had designed a virtually identical cartridge based on the 8X68 case many years ago but never got around to building it. After using this cartridge, which has identical case capacity, I see no need to continue with the project.
After much chatter on the thread this spring and last fall I managed to get it out to do some external ballistics testing on a black bear this spring, it was devastating however the 270 gn Speer was not designed for over 3000 fps so bullet performance was dismal but still managed to kill the largest black bear I've ever taken.
This cartridge would kill every animal on the planet with appropriate bullets and not be undergunned for any save maybe elephant, maybe !! I would still use it though with a 300 gn solid @ 2400 fps I have no reason to believe it wouldn't work flawlessly. All other animals would be easily overcome with this cartridge. As versatile as the 375 H&H, shoots flatter and hits harder with bullets of equal weight with better sectional densities and in any action that holds a 300 WM, what's not to love.
What exactly is it you would like to know? It is nothing more than a 300 WM necked out to use .366 bullets. I use all W-W brass and CCI 250 mag primers, any powders that work in the 375 Ruger and/or 358 NM are in the correct burn rate for this cartridge. Mine is built on an old Sako AV action and stock and has a 26" Bevan King barrel, Bevan also did the work on it. There is a lot of blather back a bit in a thread I started last fall about this rifle and cartridge.
It exceeds expectations with regards to velocity and accuracy seems good to outstanding, but I've only just scratched the surface with this cartridge. I have loaded 270 gn Speers with RL 17 and "hit the wall" at 3030 fps, ran out of bullets and then went to 286 Parts and RL 19 I think, (my data is still packed somewhere) achieved 2968 with the parts and accuracy seemed good (1.5" or so IIRC) before any tweeking of COAL or fine adjustments to powder charge.
The thread you might like to check out is back 8 pages and starts with "Bought new rifle, old Sako AV"..........................
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I didn't do the job, but I know Bevan used a 35-300 WM reamer he had and built a new pilot for the 9.3 bore, then used his 9.3 neck and throater to finish the chamber. The dies are just bored out 9.3X62 dies from RCBS, I suspect he used the same reamer or possibly a rougher reamer to bore the dies after annealing them. They work OK for now but I will probably send Fred Huntington some fired brass and have a custom set made sometime in the future if I decide to keep and use this rifle very much. Bevan has more than 150 different reamers and I have no idea how many neck and throat reamers, almost any wildcat is possible for him to chamber at this time.
