Hard lube missing anywhere makes fliers. Lube must be even all around and must all leave at muzzle exit or you have counter weights on your boolits. It is like casting with air holes in your boolits.
Most store bought will have a hard lube with half in the bottom of the box. Do you REALLY want to shoot them?
I have made more lube tests then anyone and you can go from a shotgun to one hole with a lube change.
Powder coating still scares me because what will be long term barrel wear. Are there any abrasive things in the paint?
[Linked Image] here is a hard lube and a soft at 50 yards.