I know what you mean Roskoe - I've heard the same from some very knowledgeable folks.
I can only assume 2 things.............. either the burn rate of this powder is not conducive to shorter barrels or else I got ahold of a bad batch - which for a NEW powder, is inexcuseable.
Either way, it ain't working for me - but that doesn't mean it doesn't work well in some guns. Experimentation is fun
and worth trying.