I finally found the proper mould for my BPCR, and will also order dies from Buffalo Arms in the AM if I haven't been called to work. It's not one with all the 'cowboy' connotations, but a 10.4 X 47R. The 300+ gr .429 heeled bullet also has a hollow base. While I'll most likely work up a smokeless load, I'd like to shoot it with the original load of 61 gr of FG. The questions:

What do I need to put between the bullet and the powder for optimum accuracy?

The case is made from 348. Would magnum primers be beneficial?

Is it necessary or helpful to fill the hollow base with anything - like beeswax?

Thanks! SW

Darkness is all around us and enemy are just beyond the perimeter.