What scale is it?

1/144 close enough to 1/160 for my purposes.

Nice setup =)

Freud may tell what he wants bu I just love these oversized pieces! I'm always planning to build one of those for Warhammer 40K scenarios, but I never find time, alas..:(

What, no laser sight?

Oh, dang! Dat's a big gun!

The company that produced this little beauty can be looked through here http://dragon-models.com/
in their 'can.do' section. they even offer 1/72 scale RC tanks and jeeps!

It may not be useful as military hardware, but it makes a gorgeous model. I like the long barreled types myself, and used to have a model kit of a US Army 280mm (I think) "atomic" canon. It was towed by dual tractors, though, not mounted on RR bogies. Lost that many years ago, but still have the wheels from it, oddly. I thought they might come in useful for some other model building someday, but they never did.

Oh, and the model was about three feet long. I think the maker was Renwal, that also made naval vessels, and anatomical models (like The Visible Man).