Wow, this blew up.
Ok, here's how we did it. We used deer leg bones, not sure if our points were legal, but 1 inch wide by 3 long is what we settled on (Pop read about the findings of the Ashby report.) When we had a few we'd throw them in the coffee can and put it in the campfire. When they browned we would haft them (sinew and hide glue, since bone is porous) and then we could sharpen them like steel. A file at first and then a stone. Pop even used a diamond hone or a coffee cup bottom to touch them up (coffee cups are the equivalent of a barbers ceramic hone if you get the glaze off) if they weren't sharp enough.
A 3:1 arrowhead with a cut on contact design that's sharp as you can make it requires roughly 4 pounds of force to enter a deer. I think Ashby actually got that number on a bigger animal but I'll say deer to cover my tail. Only thing is they're not unlimited use. They kinda give up after a few shots, or at least they did for us.
Some of this is stuff I'm remembering from being 13 and remembering through 5 strokes. If I had bones here I'd do a build along for you guys, but I haven't taken a deer in years. I think beef bones would work great. Thicker and flatter than deer.
Gar scales were like ready made arrowheads for fish. Little sharpening and stick them on with pine pitch glue. They're basically teeth. Really wish I had some right here. Makes me miss Pop and Gramps terribly.