Since your setup/backstop will accommodate:
3x3 post it as head/cranial vault @5y on target #1
5.5” black of a b8 @ 50y for the body/heart on target #2
Hit/miss, 7 hits for time, any position fair game but must start standing.
Start standing. 2x on #1; speed load (from bolt lock); 5x on #2.
Under 12s is respectable
Under 10s is damn good