Polymer v non-polymer...
Piffle. Reconsider the definitional domain.
What you really intend to convey is "non-metallic," like Sam'l Colt's first wooden revolver.
I recall reading a sciene-fiction story where one of the premises was that it took place on a planet with no metallic ores --their technology was based totally on ceramics, including the engines (turbines, "'bines" in the story) and firearms. Pete Coors, are you listening?
The use of polymers, in my opinion, was not "innovative" in the sense that the original poster intended, if I may put words in his/her mouth (IIMPWIHM.) It was only a new application of incrementallly advancing technology... which is what I said above i.e, David's slingshot.
Even Da Vinci's "helicopter" was an extension of an ancient Chinese toy.
And the new "heat ray" is an extension of u-wave technology.
Here's a bet for you:
The next "advance" in firearms technology will be toward short-range bullets with low sectional density, maybe aluminum, which runs pretty good on steel, driven at "ultra" high velocities, and with extremely high rates* of spin.
Can the moderators hold the bets for a decade or so?
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* I know "spin" is itself a rate. I'm just using conventional mis-terminology, as in "rate of speed."