Barrel length Wanted

some us found that the HnN bullet type pellets dont like airgun barrels particually those with chokes,but did shoot well in barrels made using 22 rimfire barrells,has something to do with them having full bearing surfaces like a bullet not liking barrels made for pellets,near as we could figure out as pellets noses made to fit bores and not engage rifling,its the skirts that engage the rifling with pellets normally,the bullet type pellets its bassicaly the whole projectile engaging the rifling,as to why in some barrels this makes a difference never did figure out,as i have custom made airgun barrels here that shoot both types just fine,proberly something to do with rifling twist or the depth of the rifling or possibly choked barrels etc just gave up trying to figure it out,i just measured several different 22 rimfire bullets they all were in the 5.56 range the HnN rabbit magnums airgun bullets i measured were all in the 5.60/5.62 range far too big for a 22 airgun barrel and evan too big really for 22 rimfire barrels to,there in i guess lays the problem and that being the case if the HnN bullets were put thru a 5.50/2 sizing die they would proberly shoot just fine in airgun barrels so must try that just out curiosity,