....... was cocked by lifting a metal "strap" which was formed around the cylinder and clipped to the back of it.

As the strap was lifted, the barrel which was around 3.5" long, would pivot downwards at the muzzle end thereby exposing the breech end for loading the pellet.

It had a wooden butt.

I borrowed one for a couple of months when I was a lad and became quite proficient with it.

Once I know what it was - photos would be great for confirmation - then I can maybe keep an eye open for one.

Thanks folks.