33 SHERMAN MAGNUM

So thinking about this more, specifically about the possibility of using 300 PRC brass. Could you neck up PRC brass and then fireform the shoulder as you could with the 30 Sherman Magnum? I'm also wondering about powders....I've got a H1000 and N570, but I'm assuming that the best performance would be with something faster burning?
 
I like this idea way better than the RUM. The RUM's are too long, they only work well with light for caliber bullets or with custom magazines boxes and reamers. The PRC case removes the rebated rim and gives you an OAL that works well with long heavy for caliber bullets. Crazy that it only took 100 or so years for someone to copy Charles Newton.
The .30 Newton had a .523" base diameter. The .375 Ruger, at the base, is exactly the same size as the belt (.532") on the H&H based cases. It is not a copy of the Newton.
 
How does this differ from the .338 Campfire or Demon I think it was? 250gr at 3000 +/- a little.


I'm genuinely asking, because when my RUM barrel is toast, it may become a .338 of some flavor.
 
How does this differ from the .338 Campfire or Demon I think it was? 250gr at 3000 +/- a little.


I'm genuinely asking, because when my RUM barrel is toast, it may become a .338 of some flavor.

The campfire is simply a necked down 375 Ruger with no other changes to the case whereas the the 33 Sherman mag is also improved. Taper straightened and sharper shoulder. Pic below is the 30 Sherman mag (33 is just necked up) on the left and right, with the standard 300 PRC in the middle.
 

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The campfire is simply a necked down 375 Ruger with no other changes to the case whereas the the 33 Sherman mag is also improved. Taper straightened and sharper shoulder. Pic below is the 30 Sherman mag (33 is just necked up) on the left and right, with the standard 300 PRC in the middle.
Thanks!
 
It's the concept of a magnum size cartridge with matching rim and body without a belt. If I remember correctly Newton did his before the 300 H&H was around so he wasn't trying to fit his round into millions of existing bolt faces, but the concept was the same. The Ruger case I would argue is the same concept just made to take advantage of the .532 bolt face that has become the standard magnum bolt face diameter.
 
It's the concept of a magnum size cartridge with matching rim and body without a belt. If I remember correctly Newton did his before the 300 H&H was around so he wasn't trying to fit his round into millions of existing bolt faces, but the concept was the same. The Ruger case I would argue is the same concept just made to take advantage of the .532 bolt face that has become the standard magnum bolt face diameter.
I believe the Ruger case is one of the best designs in the past 30 years. I dont think we needed stretched WSM's/shortened Ultra Mags (the Noslers), or even the shortened Rigby (300 Norma). A .30 on the full size Rigby case has already been done though,, the .30-378 (Roy put a belt on a 416 Rigby and called it his 378)

Anyway, some folks think its a good thing to have the market flooded with redundant cartridges. They may be correct. There is enough .308" options to catch anyone's eye!

Edit: Sorry if thats rambling on. I literally just woke up and wrote it lol not sure if I had a point or not 🤔
 
I believe the Ruger case is one of the best designs in the past 30 years. I dont think we needed stretched WSM's/shortened Ultra Mags (the Noslers), or even the shortened Rigby (300 Norma). A .30 on the full size Rigby case has already been done though,, the .30-378 (Roy put a belt on a 416 Rigby and called it his 378)

Anyway, some folks think its a good thing to have the market flooded with redundant cartridges. They may be correct. There is enough .308" options to catch anyone's eye!

Edit: Sorry if thats rambling on. I literally just woke up and wrote it lol not sure if I had a point or not 🤔
I totally agree, that was my original point with the Newton reference, he came up with the idea in 1913 or something like that and it took almost 100 years for someone to make it commercially relevant. It is a case design with no compromises, it is designed to optimize long range bullets in modern actions, no rebated rims, no useless belts, nothing that it doesn't need.
 
OK, I finally got a LITTLE bit of data by building one myself. Its my old 24" 338 Sherman barrel that I rechambered.
I will be cooking up some loads for testing soon, but currently finding where pressure is with various powders with 250 and 300 Bergers.
I shot the 250 today With RL26 and reached 3105". No x mark or heavy bolt, but guessing I probably would have with another grain.
I tried N570 with the 300 grain, even though I knew it was likely too slow to pressure out. I did reach just over 2700 with no pressure but can't get much more in. Ill be trying N565, Retumbo, and maybe 8133 yet.
 
OK, I finally got a LITTLE bit of data by building one myself. Its my old 24" 338 Sherman barrel that I rechambered.
I will be cooking up some loads for testing soon, but currently finding where pressure is with various powders with 250 and 300 Bergers.
I shot the 250 today With RL26 and reached 3105". No x mark or heavy bolt, but guessing I probably would have with another grain.
I tried N570 with the 300 grain, even though I knew it was likely too slow to pressure out. I did reach just over 2700 with no pressure but can't get much more in. Ill be trying N565, Retumbo, and maybe 8133 yet.
 

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