I have my 870 broken down, ready to apply duracoat, wondering what I should mask off and how

What all you planing on shooting with DC?

Barrel, receiver and magazine.  I don't think I'll have too much trouble, but I want to make sure I don't screw up any tolerances.

I did my 870 and the only thing i taped was the end of the barrel where is goes into the receiver and put some newspaper into the receiver itself so it wouldnt screw anything up.

I just said the hell with it, sprayed it down, doesn't look great, but good enough for my purposes.  Thanks!

Does dura coat have to be heated after being applied like some of the other spray can finishes, and how durable would it be for something like hadgun mags.

Quoted: Does dura coat have to be heated after being applied like some of the other spray can finishes, and how durable would it be for something like hadgun mags.

No it doesnt have to be, but you can "speed" up the process. I don't bother, because even though it appears okay to do, rather let it cure naturally.  Per Duracoat: DuraCoat will dry to the touch in 20 min and can be used after curing 6 - 8 hrs. How ever it will continue to cure for 4 to 6 weeks after application.

Pertaining to mags.  Well, I've used Brownells Alumahyde on some old Sten mags as well as regular AR mags.  Surface prep is important, totally degrease and I've had no excessive wear on those mags.  As for the finish, I do feel that there is more durability with Duracoat than Alumahyde.