Locks up perfect with no shim on an oddball SB2 that locks up with nothing else I own. No gap, cannot see light, release has normal wiggle. Latch contact is a match head size spot on the corner of the latch at a burr. Filed the burr off. No additional contact. Nor did contact point move. Still locks up fine. I do not want to go too far. Have not shot it, actually have no ammo yet. Thoughts?