#9 shot is probably the most popular shot size in all gauges for skeet shooters. #8 and 8 1/2 shot also works well at skeet.
#9 shot will also work for 16 yard trap, but it is not very popular. Most trap shooters use #8 or #7 1/2 shot for 16 yard singles and #7 1/2 shot for the longer shots in handicap trap.
