What case length should 450/400 3" cases be trimmed to? The A-Square manual recommends 2.990 while Pierre van der Walt recommends 2.830 in his "Big Bore Cartridge Load Data Collection" book.

Mike Chamberlain

I trim to 2.990". I have no idea where van der Walt is getting his figure. Fleming's book indicates that the shortest case encountered in vintage Kynoch ammunition was 2.983".
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"Serious rifles have two barrels, everything else just burns gunpowder."

My copy of Pierre's book came with an errata sheet that corrects the typos in the book. One of the corrections is on the trim length of the 450-400 to 2.992".

Pretty much all the rest of the typos are also on trim length.

The only potentially hazardous error is a powder charge correction using Tubal-5000 powder in the 375 H&H. "Reduce max to 71.0 grs"

Thanks guys. I kind of thought thought Pierre's trim length might have been a typo, but I really appreciate getting the info from you folks that have actually loaded the round.

Mike Chamberlain