I don't have a 300 H&H but I do load cast bullets for 300WM. My first choices would be 20-24gr of Unique as a starting point or a 70% capacity load of Trail Boss. Somewhere around 30-35gr of SR-4759 should also work well.
Thanks for the info. I've been looking for the lyman cast manual but can't find one. On the load of 15-18 g unique, is that starting load? And what is the fps on that? You don't use any fillers do you? Do u still use magnum primers? ThanksAs the above poster said, Trail Boss, impossible to overload the case as long as you do not compress the powder. Easy to work up a good load. That being said here is the data from the Lyman cast bullet handbook for a 151g bullet.
Red Dot 12-15g
700x 12-15g
Green Dot 13-16g
PB 13-16.5g
Unique 15-18g
SR7625 13.5-17g
630 18.0-22.0
Hope this helps.
As the above poster said, Trail Boss, impossible to overload the case as long as you do not compress the powder. Easy to work up a good load. That being said here is the data from the Lyman cast bullet handbook for a 151g bullet.
Red Dot 12-15g
700x 12-15g
Green Dot 13-16g
PB 13-16.5g
Unique 15-18g
SR7625 13.5-17g
630 18.0-22.0
Hope this helps.
This is complletely different than the information in the First Edition of the Lyman handbook of cast bullets.
For the 300 H&H, 150 grain cast gc bullet, they show eight different powders, from fast 4227 to the very slow 4350.
No Unique is shown.
Examples are 35 to 46 grains of 3031 and 41 to 51 grains of 4350.



























