I am still roughly a year out on getting this one finished, but thought I would start looking now for load data, as it is pretty hard to find. The chosen projectile at this point is the now discontinued Barnes .411" 400-grain flat based "X", and I will be using new brass from Huntington Die Specialties. I also anticipate trying some of the 400-grain Woodleighs at a later date, if that helps.

I know if push comes to shove I can call Barnes, or send dies, bullets, and brass to a powder supplier and have the loads worked up, but would really prefer some sort of "jumping off point".

Thanks in advance...

I know this thread is ancient, just throwing this out there in case yourself or others may be looking for some load data.
Just picked my new 400 H&H up from my Smith yesterday, it's built on a G series M-70 classic action that was a 300 RUM I torched the throat in, it wears a 25.5" Krieger barrel.

I started at 70 grains of Varget under the 400gr Swift A Frame and Woodleigh solid of the same weight, topped out at 75 grains, the A Frame ran 2408 fps the solid went 2425 fps.

Will put em on paper today, brass for the soft point is Quality Catridge, the solid brass is some old H&H Cylindrical Norma my Smith picked up at a gunshow for me, loads were lit with FED-215 primers.