Primitive Archer

Not sure what you mean by "fire hardening".  Heat-treating is essentially the fire hardening of wood.  If not done properly though "heat-treating" can be nothing more than changing the surface wood's structure and that really does nothing for a bow.  Proper heat-treating of a bow is a process that takes several hours to do.  Osage and BL certainly benefit from heat-treating but they react a bit differently to heat and you have to keep a close watch on what's happening with the wood, I suspect it may have something to do with the oils in the wood

The guy who found the bow in Chattanooga bought it, I letter all of my bows so he tracked my name down and asked me about the bow. I keep a log book on the bows that I have made but the glue line in the handle was a dead give away on this one. URAC 185 was the most amazing glue I ever used, I used it in this bow fix.

The bow as found in Chattanooga;

 

Arvin's patch leaves a lot of non bending wood below the patch to keep the handle section stable.

I would be surprised if your patch doesn't turn loose, you removed a LOT of the strength of the handle, I hope I am wrong. Even non bending handles stress and bend some even if it is a small amount. I have tried patches in the limbs, the patches would hold up for a couple of years and then turn lose.

I glued patches into this this handle just of see if I could get away with it because the rest of the stave was really good osage, I bamboo backed the bow to add a another layer of stability to the handle. I sold the bow cheaply, 15 years later it surfaced in an archery shop in Chattanooga, still in shootable condition

I started with this;

No Yot for me WB, didn't eat this cat either but have eat Bob Cat back strap, Eddie Parker brought some to a hog hunting camp one time, it wasn't bad but I didn't go back for seconds. Ya that would be cool Bob, wished I was a sewer, may talk to Becki Parker and try and make a trade.  Got to get it stretched and tanned first. Going to try and brain tan , I have done some mink/coon and they turned out OK, tough to brain tan , hair on or at least it has been for me but this hide is pretty thing so we will see how it goes.
 Pappy

Thanks guys, ya Little John I usually manage a deer,just can't seem to put together an Elk. 
 Pappy