Need some help from a Belgian A5 expert! I've located an A5 16 ga. in pristine condition, definitely bearing only Belgian origin markings, but there is a dilemna. On the left side of the barrel, it clearly says: cart.- 2 1/2, which I believe indicates 2 1/2 inch cartridges. On the string of other proofs along the left edge of the barrel, it also bears the greek symbol within which is: 16-70, which I believe refers to 16 ga, but 70mm (or 2 3/4 inch) cartridges. Is this a riddle? The challenge is, I have only 67 mm cartridges available here, so if it truly only accepts 2 1/2 inch shells, then I'm sunk. Also, on the bottom of the barrel is marked 16.6; which seems an odd barrel diameter to me, but perhaps it refers to a full choke? Please feel free to provide any and all expertise and advice. Thanks!