I have 4 sight screws holes in a barrel that I am going to fill with 6x48 plug screws. My question is whether I should install the screws before or after duracoating? I am afraid that if I shoot the coating over the screws I might end up with a bad edge around the holes if I remove the screws. I don't know if scoring around the screw before removal with an exacto knife will help.

What is the best way to handle this situation?

Also, is it better to shoot the barrel and receiver separately or assembled. If assembled, will baking it at 200 or so degrees be enough to sweat out the anti-seize before coating?

Actually it looks like it's going to be matte black Aluma Hyda since I have a can of that already on hand.

Curt,

I know very little about the applied coatings to which you refer. I thought about your question as it were my rifle. My conclusion is to install the screws, time the slots and coat over. More likely than not when you do have occasion to remove them it will suppose a sight base install. Any slight burr around the hole will be covered.
Just a thought.

Luck,

Stephen

Don't coat over the screws if you want it to be a quality job. Coat the screws separately.