I have been reading up on the .458 Lott it seams to be one of the ultimate Dangerous Game cartrages. Any way brass is pretty expencive on average in the relm of 1.50 to 2 bucks a peace. I found out that the parent cartrage for the .458 Lott is the .375 H&H mag. .375 H&H mag is conciderabley cheaper than .458 Lott brass. I have found case forming dies on the internet. What is the process to case form from .375 H&H mag to .458 Lott? Also if you form cases from .375 H&H mag to .458 Lott what are the disadvantages? If I can get 4 shots out of a .458 Lott will i get less with cases that where fromed from .375 H&H?

I also found out inadverdantly that the .300 weatherby and the .340 weatherby where based off the .375 H&H mag. If you had a hard time finding .340 weatherby brass your could form it from .375 H&H.

Thanks

I have never done that conversion. I would "think" that a expander somewhere in the middle would be a big help.

Neck up a little(0.40?). Then neck up again to 0.415. Then reform the shoulder a little at a time by turning the die down a 1/2 turn a time WITHOUT withdrawing the expander until sizer is in contact with the shellholder.

Good dies and case lube helps alot when doing case reforming. I tend to wreak a few til I figure out what I can get away with.

Cheezywan

Check out RCBS's case forming dies, they may have a set already made up.

Zapzoo,

if you use a tapered expander button like Hornady's Eleptical Expander and coat the inside of the case neck with a very thin film of Imperial size die wax, you will not have any problem necking up the 375 H&H case up to the 458 Lott in a single pass as this is what I have just done myself...

Like you mentioned, the 375 H&H is an excellent case for making 300 and 340 Weatherby brass from as I do this on a regular basis.....

A

Imperial Die Wax is the best case lube just keep the excess off the shoulders to prevent "lube dents". I would assume that you may actually get more re-loads from a formed case. Also, 4 re-loads is not many. You may get more if you go to neck sizing only.

Zapzoo, you're timing is pretty good. I'm going down from .375 H&H rather than up as no one has or is making 300 H&H brass. MidwayUSA has a good price right now on Rem .375 H&H brass and I just got 100 in, now I'm waiting on RCBS to make me a form and trim die.

Keep us posted on how it goes.

Another thing to look at on getting more re-loads out of that brass is headspace. Make sure you're good. You don't want a case head separation.