Easy- the steel plate is readily visible where the shot impacts, just not the high contrast you get with white pigment. Was able to easily see the horrible patterns (I had already suspected) in my #4 non-tox reloads, and the amazing regulation of my third set of tubes fitted to the Manufrance 314. The smith humbly claimed the regulation was by accident (he fitted, finished, and opened the chokes on these in the white barrels), but I still give him credit and couldn't be happier.
Whatever you put on your plate, you and I know that while the information derived is incomplete, it is still invaluable.
Mike
