Back in the day I was using a thrower on Varget and load a round very short. Bullet did not leave the barrel. Damn glad I heard something wrong before I fired again. These days I measure with a Hornaday auto measurer not sure that is the name but ever round in load when in a .1 gr. sure does take longer but all,is right.I think at subsonic levels not enough powder to do much damage except send the pill down the barrel, may go supersonic worse case scenario.