At times I have too much time on my hands and Get to playing around with the loading dies and my lathe and such trivial stuff. For example, the other day I got a bit bored with the repair work and got playing a bit and necked the .300 short mag up to .458. Now this new (AT least for me) creation will hold 69 grains of IMR 3031 to the base of the shoulder so it should equal the .458 Winchester. In a Mauser length action even with heavy bullets you can seat them out far enough so you do not loose case capisity, un like the .458. What do you think, have I founf a usful use for the short mag case?