Re: Barrel length and powder burn rates?
H-1000 is going to be way too slow for a 22" barrel. It's actually a bit slow for the 190 in a 300WM unless you have a super long barrel 30"+ and are loading compressed loads.
I haven't loaded for a short barrelled 300WM, but according to Quickload, a max load of H4350 will be 100% burnt in a 20.5" barrel behind a 190gr bullet. 22" barrel should work fine with h4350. Should be able to get around 2900fps with it.
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