I spray inside if I'm doing a full length size with an expander ball, which is all of my 300BLK and 5.56 brass. With my precision rifle rounds in 6CM, I use a neck expander mandrel instead of the expander ball and use graphite, so I don't want lube inside the case.Like the nail board idea. Looks like I got myself a project.
On a second note, when do spray inside the case?