BD is pretty slow, close to the burn rate of full-power loads. Seafire's rule may apply, but I don't know. I'd start at 40-50% case fill, fire one, go from result. Seafire's rule defines max load as 60% case fill with BD. I've tried it in 223, 243, 30-30, 30-06. I stick closer to 50% case fill. Wasn't what I was after, but it worked.
