There was a thread started by Doc Rocket back in 2012 about modifying brass to make handgun shotshells for .45 Colts and .44 Magnums. This is done by modifying other brass to fit the chambers. The thread initially dealt with making these shotshells for a .45 Colt. Later in the discussion, it was said that for a .44 Magnum, they could be done by modifying a .445 Supermag case. The supermag case does not need to be shortened, but the forward .30" or so does need to be sized down to fit the chamber throats. The overall case length is fine for the chamber, thereby using the most room for a large shot load. It was said that these supermag case ends can be sized down properly by using a .40 cal/10 mm sizing die. The outside diameter of a .445 SM case is the same as a .44 Mag case, .456". The throats on my .44 are exactly .430". The outside specs for a .40 cal case is .423", so this should fit just right in my chamber throats. Now, my problem is both times I have tried to run a piece of .445 SM brass into my .40 sizing die, I have crushed the case. Anyone have any ideas how I can downsize this to fit a .430" throat? I only need about .30" of the case end downsized. I have tried unsuccessfully to contact Doc Rocket about this problem. He and others have done it, so I know there is a way.
Last edited by Henryseale; 03/29/21. Reason: punctuation
