Type 4 Magazine

I built my own Type 4 magazine. I started with a 16 in. x 20 in. x 6in. x .062 in. wall thickness Hoffman steel electrical enclosure from Boeing surplus. To increase the wall thickness to the required 12 ga., I cut six pieces of 16 ga. (.062 in.) steel sheets and attached them with pop rivets to all sides. The interior is lined with a thin indoor/outdoor carpet for the non-sparking requirement. I installed two deadbolt locks from http://www.cainsoutdoor.com/cart/asp/select_item.asp?item=02979 . Important: these locks are approved as mortise locks by the ATFE. Conventional cam locks from a hardware store will not qualify as mortise locks.

My magazine is bolted to the inside of a garden shed on my residential property.

Cain's also sells complete magazines http://www.cainsoutdoor.com/cart/asp/select_item.asp?item=02981 . I think this is the same magazine Magnum sells.