Well i looked but since i'm no expert i got nowhere. Looks like i may also be wrong. Here is a link to show why i may be wrong.

http://www.browning.com/customerserv...tail.asp?id=90

To be honest the 777257 number on the bottom of the barrel doesn't correlate correctly to anything i can find. That serial number if that is what it is shows it would be a fairly newer gun no older then maybe 30 years but has no other indicator. That could have been something a gun smith added to it themselves. Hard to say for me at least. If its a later model the stamping would be more machined then hand etched. Nearly all hand etched markings though don't show up like that they also have other markings to go along with them. This is a link for other markings for the Europeans makes to see if you have them.

http://damascus-barrels.com/Belgian_All_Proofmarks.html

Definitely not an A-5 though.