I did them inside and out. I drove a rod into a handy oak tree, I slide the magazine body onto the rod, and spray away. Don't get too close, make even, overlapping passes with the finish. Shake often and apply a thin coat to the interior. I do not do the springs and of course not the followers. The floorplates are laid out on some cardboard and sprayed. All are allowed to air dry. I look them over for runs or missed spots in the finish. If they are OK, I put them on a coat hanger I rigged up and bake away. The finish looks good, is durable, is not a real chore to do, and is for damn sure cheaper than sending it off. If you are really into it, you can get an air brush and spray GunKote on. Brownells sells it also. You can get bigger cans of the epoxy finish and use an air brush as well to camo finish or whatever.