"semi-poly" frames

[Forte S+W]

Technically, a lot of frames are hybrid frames these days due to the implementation of metal chasis within the polymer frame to extend their life and reduce flexing.

The Smith & Wesson M&P Series and Ruger LC Series for example have such metal chasis imbedded in the polymer frames.

 

[Jim Watson]

Wilson had two different plastic 1911 mutants.
The KZ series and the Spec Ops 9.
Wilson still carries KZ9 and Spec Ops 9 magazines but if you have a KZ45 you may be out of luck.

 

[FrankenMauser]

The Smith & Wesson M&P Series and Ruger LC Series for example have such metal chasis imbedded in the polymer frames.

They're pinned in, not embedded.

 

[Aguila Blanca]

It was the KZ-45 I was thinking of.

https://www.handgunsmag.com/editorial/featured_handguns_wilsonkz45_032807/138813

 

[Big Shrek]

I think the very first hybrid pistol was the Star Ultrastar model 205.
Has an unusual metal skeleton frame wrapped in polymer.
Also has one of the most interesting slides I've ever had.

Both the 9mm & 40 versions are a true joy to shoot.