The Rolling Block Rifle was one of Mattel's distinguished line of Shootin' Shell weapons. It was sometimes packaged alone (with a cowhide bandolier - not shown because I don't have one) and sometimes with a Shootin' Shell Fanner 50. It was modeled after a real Remington rifle fitted with a rolling breechlock between the hammer and the cartridge. Because that sounds a little complicated, it was also called (at least on the box) an "Indian Scout" rifle.
More Cap Guns HERE.