well it is all in the "semantics" but in truth, rubber that is hardened is "plasticised" the rubber of old Colts and such was pretty much "rubber" , it was actually 'gutta percha' a form of rubber.......old man Ruger called his grips "hard rubber", cause "they put plastic ones on cap guns.." I do quote Mr Ruger.........yes, the first, early grips used by Ruger on their RST's ,semi autos, it was 'rubber' , called ""butaprene",the Single Sixes ala 1953-54, they"hardened" the material used for the SingleSix and the flatop 357's, heard tell the first ones they put on the 44 flatop, did not fare well, broke, and hurt the shooter,so went to walnuts the next week??)last week of Nov 1955, and the first week of Dec. or was it 1956?? I was a young lad, and 'ferget' 8)
One of the Dr types we worked with at GE , who used to chat with us from time to time taught "polymers" in college, worked for Goodyear or Firestone it was , here in Akron,Ohio and went back and forth from GE Plastics to our plant at Nela Park, and yes, he was a 'gun nut' so we'd talk, he told us, as to the process of rubber being "plasticised" ( hardened) and I bet you could Google it.....rubber, too soft, wore and warped, plastic too hard chipped, so there has to be a proper middle..years ago I spoke with the folks up at Bar S grips over in Evergreen Wa. they "poured" ( molded) grips and did a fine , dandy job, made "ivory " like grips in about 5 shades of "ivory" and we liked them........also knew the first owner of Ajax Grips , years ago, and they made LOTS and lots, still do today, and yes "polymer" is pretty good stuff, "on paper"....... 8) :roll: :wink:
so call them what you want, makes no matter to many of us, heck, the new ones, some folks call "cheese graters" ........................ :)