I use the RCBS measure without problems.

Q? what is wrong with your Lyman measure? Is it worn out? What kind of spreads in weight do you get with it?

The reason I ask is that in rifle cartridges, especially with extruded IMR powders, people seem to get concerned about not having exact weights in each powder charge. The best I can get with IMR powders is about +/- .25 gr. While this might not be accurate enough for some people, its more than accurate enough for a rifle cartridge, in fact measuring volumetrically can actually produce more accurate ammunition than weighing each charge exactly.