Borepatch has discovered the Evans rifle. I should have bought that one I once saw at a gun show for, like, $499. I bet the guy would have taken four and a half to not have to carry it home with him.
When the Calico carbine came out with its helical magazine behind the action, antique collectors just looked at it and thought "Huh. Just like an ol' Evans." (Similarly, the new Boberg XR-9's exotic shell elevator loading system? Webley Mars.)
There is very little new under the sun when it comes to firearms. Since, oh, probably the 1930s, the only advances have been in materials and construction techniques. Armies today are still using gas-operated, rotating bolt, brass-cased smokeless powder self-loaders, just like they were 75 years ago. The machine pistol has come and gone.
This is a very mature technology.