Not sure if this si the appropriate sort of forum to request this kind of advice. If not, please redirect me somewhere more suitable.

I want to construct this model gun from sheet metal for laser-tagging purposes. Given that the diameter varies along the length of the gun, how might I accurately fold the metal? And ideas for making the gun handle, which I'd like to construct from the same metal? The blue part is a plastic window.



The only idea I've had is to make a solid gun barrel shape from wood and then fold pre-cut aluminium around this scaffold. I don't have a lathe and don't know when or if I'd be able to borrow one (I don't want to buy one for various reasons) so is there some other method or material I might also consider to produce the required shape?