I've been working with a Borton-Darr 30 caliber 185 grain mold for a while now, and had a bit of trouble casting good bullets fast at the beginning. Thanks to advice from Jim Borton and Jim Britt, I've got the process under control.
Yesterday I cast 116 bullets. Two had visual defects under the 4X magnifier, one weighed .8 grains above the average, and the 113 others weighed average 182.3 grains with a standard deviation of .078 grains.
This is as good as any mold I've cast with, and better than most.
The secret for me, with this mold, is to cast HOT. The alloy is at ~825 degrees, it takes a while for the sprue to harden, and it takes about an hour and a half for me to cast a few over 100 bullets.
These bullets are extremely accurate in my guns, more accurate than any other to date..
Thanks to all for the advice, and to Jim Borton and Barry Darr for this mold.
joe brennan