I have put turkey feathers on the back of an osage bow I built for a buddy. I had put feathers on turkey calls i'd made in the past and thought it would look good, Looks like other people thought so tooo. Theirs look real nice. I used what is called Flex Coat a two part epoxy used for fishing rod guides. First step is to get all the feathers needed to do the job before you start and lay them out on the table some what like they would go on the bow limb. I think there is two types of FC one thick and one thin, I use the thin. Apply about three inches on the bow at the tip and layer the feathers down like shingles one at a time. The trick is not to break apart the feather as you lay it down and as you apply another thin coat on top of the feather. I use a very soft hair brush and brush the thin top coat on very gently. Keep repeating the process a few inches at a time. The FC takes a long time to cure. so keep an eye on it until it begins to set up. by that time some of the feathers may raise up off of the bow especially on the edge. When the FC is tacky I use my finger and push the feather down around the edge. After both limbs are done and dry, I use a sharp fine file to cut off the feathers overhanging the edge. very similar to the way I do rawhide or skins. One final thin coat of FC over the feathers and your done. I has a super gloss finish. I have buff it with steel wool to make a satin finish.
I did not have enough feathers to do the whole bow back. That is why I mention to lay out your feathers before you start. I'm work on a molly that I'm think about putting feathers on the working part of the limb.
Good luck, and drop me a line if you have any questions.
DBar