Sorry about this report as i have no idea about any of these things!
Was doing another explore when i came across this and i no people go mad for these. Found at Brackenhill Quarry. It's called a 'magazine' and is full of unexploded bombs basically. Sorry for info, no idea.
Notice by KelseyRebecca98, on Flickr
Magazine by KelseyRebecca98, on Flickr
Magazines by KelseyRebecca98, on Flickr
The Magazines by KelseyRebecca98, on Flickr
Thanks for looking
Flickr: http://www.flickr.com/photos/kelseyrebecca98/