[Unclenick]

Neither IMR nor H 4831 are suitable or recommended for reduced loads. This is why you don't see them listed at Hodgdon for bullet weights below 175 grains, and even then the minimum charges are in the low to mid 50's of grains and the maximum charges are compressed. Slow powders do better when the case is more constricted, as with a .270, letting them build pressure better. In low pressure loads, ignition becomes erratic. I've seen cases full of the stuff that squibbed out, leaving a bullet stuck in the barrel. I also seem to recall early reports reports of detonation were with light charges of surplus IMR 4831, leading people to assume that phenomenon only occurred with slow powders (later reports suggest this is not so).