I'm not certain. Perhaps it because the shot transitions the lesser constriction with less disruption. Why does using one hull seem to produce better patterns than a different brand? I gave up trying to figure out why, and just accept that it happens.
All the patterns below were fired through a .705 Terror choke, which was designed for steelshot and used a 2 oz. handload, which was nothing special, just picked out of the load manual. The Hevishot load was a Remington 2 oz. factory load.
40 yard patterns with 4 buckshot.
Lead BB's
