push threw 6 peppets threw bore measure all 6 get an average size and add .0005 . this will give you the proper size you need also when pushing a slug threw barrel if it waqs proper size should take about 15 to 20 pounds pressure to push threw barrel , this will insure proper size so barrel wont foul up with too large a slug or not spin properly if it were too small
LOU
PS I have many 22 cal slug pcp s and they shoot between .2155 to .219 depending on gun , their is no one size fits all , even with same brand you will find no 2 exact , and some barrels unchoked some choked some std rifling some poly some rounded rifling some square cut , so each one prefers different ammo ,
and naturally once you get size proper for slug then twst rate will determine which slugs will shoot stable , their are a few good online ballistic stability apps , then you set power for what you shooting ,
