If you had any understanding of the purpose of the crown was,you might understand.
The bore diameter along with the hardness of the barrel, there is .003-005 difference in the two diameter we are working with here,it would take an idiot to screw it up.
Simply lapping the crown with a soft brass screw and some compound would likely point out the high spots that could be causing your issues.
As simple as it is, to some its still way over their heads.
