Wasn't looking to double down on post just pics were on phone. I really have to say that Ultimak is an awesome company to deal with.
Ok also going to add possible two buffer pads. As I am pretty cheap I will be trying to use them toilet washers. Testing for chemical resistance to gun oil and solvents. Will also try to test heat resistance. Going to start pretty thin with 1/4 of an inch. Hoping with acustand rail accuracy will be good.
I figured if no one adds more to this I'll just keep modifying my post.
The chemicals tested were Hopps #9, foaming bore cleaner of some type, gen. gun oil, and break free clp.
So far as expected the solvents ate at the rubber but only caused a gumming on the surface no great material break down. The oil seemed to make it sticky put not break down. Satified with this results I would OK the use of rubber materials if vulcanized on the rear style buffers. That said I will move on to possibly heat testing next.
Thinking of getting a high temp. kitchen spatula in silicone and shaping it to make a front buffer. I expect to only need a relatively small amount of shock absorption in this application since well its all spring energy returning.
Range testing soon. Will see about starting accuracy then.