Barrel Bore size to Ball Bore size

with a flatline barrel ou want the smallest ball
possible so it can get a good spin on it. you also
need good paint, not brittle, out of shape,or dimpled
try marbalizer or evil for flatline barrels. but on any
other barrel, you want to fit the ball to the barrel. put a
ball down the barrel. if i falls straight through, its too
small. if you die blowing it out of the barrel, its too
big. you want it to fit snug, but not too snug, loose,
but not too loose. i dont really now any other way t
explain it.hope this helps.

Edited by 20700134

Don't mean to repeat 20700... but just want to stress the fact that the
flatline is the only barrel that you want a smaller bore to shoot through it.
The flatline is a large bore barrel and you want small - medium paint to
shoot through it so that the ball is only in contact with the top of the barrel.
Paint will break in the flatline if it touches the bottom of the barrel as it
starts to spin out the barrel.