Taking Daryl's advice (bigger balls, tighter patches), and using my usual GM .40 barrels, I changed from .395 balls to .400 balls, retaining the .21 or .22 pillow ticking patches (with spit), and managed to reduce by 50-yard groups by about half. Takes a bit more "whack" to get the .400 ball started into the barrel, but it's worth the bother. -- paulallen, tucson az