A good plinker is 15 grains of trail boss behind a 405 lead flat nose. Fairly accurate in my buddy’s Ruger no.1 and goes off like a pop gun.
I only use 300 grain bullets, for minimal loss of meat and hide damage, thus I am able to set my scope once and can shoot solids or softs for a variety of US game, African Plains and Dangerous game.
Trail Boss is an extremely bulky powder that most likely fills the case at 15 grains. It's made specifically for light loads in large caliber rifles and handguns.Your Original Post asked for .458 WM pet loads.
I, and some other AH members may, interpret you are asking for pet .458 WM (and/or .458 Lott) loads only. Exempting the 45-70's.
I still question the 15 grains Trail Boss, as my manuals don't list that powder as appropriate for any of the 45-70 rifles.
Although I have read that some reload the shorter 45-70 bullets in the .458 WM and .458 Lott when compressing powder loads.
I personally can't recommend doing this. There is just to much that could go very wrong. But, that's just my opinion.
Trail Boss is an extremely LOW density powder that most likely fills the case at 15 grains. It's made specifically for light loads in large caliber rifles and handguns.
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