Great link Roy!
That's a tremendous amount of raw data and a good read.
For our purposes, I took notice of the thermal conductivities of the different materials in comparison to the 4340 steel and the results that showed the area immediately in front of the throat as having the highest recorded temperature readings.
What that information tells me is if we were pursuing perfection here instead of mere betterment---OR---we were looking to obtain maximum barrel life regardless of cost involved, then a non-uniform coating thickness would be required ensuring that the coating would be at it's thickest in the pre-throat area and becoming thinner as it's moved forward toward the rifling.
Truth be told though.....this idea of a throat/chamber coating seems to have merit, but are any of us equipped well enough to do the proper R&D on a donor rifle to find out how far this takes us?
As far as devins' idea goes of making an insert.....that's probably a better solution in some respects. Although cost prohibitive on a commercial level, it definitely seems to have a great deal of potential.
Yo devins.......do you think perhaps instead of a bonded insert, that maybe there is a coating process that could work just as well---even if it's life was shorter? What I'm driving at here, is if we could possibly combine ideas so that we could coat a part that was easily replaceable (like the throat idea I posted above or similar), while leaving the rest of the rifle unchanged, then we could simplify AND save a great deal of cost, in R&D.
For instance-----machine 5 identical replaceable throats (if such is feasible in a rifle platform). Then we could test each one with different coatings and establish a useable life. OR we could choose what seems to be the most promising coating material in the beginning, and test differing thicknesses, again testing for end of life.
I believe that the second idea of choosing only one coating would allow us to significantly improve throat life while keeping costs within the stratosphere.
Come on folks.....chime in!!