I've only poured one batch of the 320's. The main problem that I had was avoiding a void in the base of the bullet. As lead cools, it shrinks. When my technique was not good I got the void. As usual, when all else fails, read the instructions.
The bullets without the void were not quite as accurate as no excuses bullets with the same loads. However, this is probably due to my poor casting technique and differences in bullet weight.
I have not had a chance to pour another batch. When I do, I will sort the bullets by weight.
Be sure to follow the safety precautions as well as the casting instructions.
Good luck!
Allen