I recently shipped a small single-shot without stock and the item fit inside my barrel shipping tube--3" OD PVC with one cap glued on and the other taped. About as sturdy a container as one can ship. UPS wanted an additional $20 because of "irregular shape" for a total of $54. I said "no thanks" and took it too USPS for 3 day priority. $30 and it got there in 3 days. I've probably used the same tube a half dozen times shipping barrels off to Mike Orlen for choke work. I tried scraping off the old labels and bar codes with mixed success and ended covering them up with gorilla tape. It had so many labels and scuff marks on it that it reminded me of an old Victorian steamer trunk covered with shipping labels and destination decals. Gil