Well color me impressed. It makes sense why you added the sinew then. Glad you got some positive gains from it. That's good knowledge to keep on hand. I also heat treated my bamboo belly but I did it by putting the two belly lams ( one for each limb ) into an oven and baking them at 400 until I chickened out, I mean, u til they were golden brown. That bow is narrow but way to stout.
Id not say osage core is a GOOD idea, it's just kinda how it happened for me. A lighter weight wood would certainly be a better option. I had a bow I didn't like so I boo backed it. It turned to be a dog, so I decided to grind the belly down and do a boo belly. It's so heavy now I just let it sit in the closet. The bow is too narrow and the recurves made it unstable. I had to cut the recurves down to keep them from twisting, but of course, that made it even stronger. I think it's around 60@26? I prefer 45@26.