I was working with BE in the 1.5 to 3 grain range for a 7.7 Jap and a 100 grain .312 boolit and found that below 2 grains it became position sensitive. I have been using a very small pinch of cotton to keep the powder positioned in the bottom of the case with no problems. When working with the extra light loads proper neck tension is very important, I got some key holing with looser necks along with no accuracy at 15 yds.