INFORMATION:
Looking into the butts.
Inset:
1. Damage done by bullets hitting the walls.
2. One of the several bays that would have been filled with sand.
3. Full rear view.
4. Rear view close up of the openings to remove used sand and spent bullets.
5. View into one of the bays from an opening in the rear.
6. Several tie downs are set into the parking area to hold the planes whilst firing.

Above : Spitfire firing into a gun butts.