Here is the same gun, it was the one I was trying to get last year, but couldn't pull it off, has pics and info towards the end, under my postings, not Marc's postings, the other is his.
http://www.mapleleafup.net/forums/sh...ad.php?t=15479
http://www.imageevent.com/gazzavc/6pounder
It is a 40 bofors, modified to fit on the barrel, fires 40mm blanks, the extraction/ejection handle and firing mechanism is on the right hand side. Paul got a great deal on this AT gun.
gun in action:
https://www.youtube.com/watch?v=tWW8yHjnKn0
https://www.youtube.com/watch?v=UwoQEdhXPD0