I use trimmed .454 brass in a Contender which works well. A couple of grains less capacity, but I work up loads so that's okay. Cases last forever.

Firing a .375 JDJ in a .444 or a .338JDJ in a .375 will cause no safety hazard. The bullets are smaller than the bore so pressure and velocity will be way down.

Don't let the armchair experts tell you it is a bad idea. The practice is not unsafe, IHMSA shooters used to shoot thousands of .223s in their 7 TCU barrels to fire form them, never a problem.

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Last edited by Carpe Diem; 09/03/2016 1:50 PM.
Based on total trigger pull weight, my trigger finger has lifted well over 200 tons....