Shot the 308403 boolit in my 300 Whisper bolt gun this weekend.
This was my first attempt at any kind of accuracy from a cast boolit. This was water dropped 50/50 pure lead and wheel weights with tin added. They were pan lubed with paraffin/bees wax/Vaseline. The group shown was at 50 yards from a bench with a bipod. Load was 14.0 grains of H4198 with a CCI41 primer. It measured a touch over 0.900". I know that barely less than 2MOA but I'm OK with it for a first attempt.
Read more here about the bullet:
http://castboolits.gunloads.com/showthread.php?t=61019
http://castboolits.gunloads.com/showthread.php?t=87479
Designed to be seated by hand in an unsized case.