I really like mine I have owned it for 25 years, they make a great rabbit and bird gun to carry all day..This one looks like the buttstock may have been replaced but I cant really tell..Great guns !
Why would you say that? I'd appreciate it if you would not comment on things you do not know about. The buttstock color and condition matches the forearm and the screws don't appear to be buggered, so I would lean towards the fact that the gun is all orginal. Some older A5s had square knobs, some had round...there is no way to date an A5 by its wood.
Weight: I can't find a definitive chart on the weight, but there is some internet chatter of it being ~6 to 6.5 lbs. Since it's a "Z", that denotes "light twenty" even though it has "twenty" engraved in the side -- my research says the Belgians were only engraved as "twenty". I do have a similar Japan 20g A5 engraved with "light twenty".