I have also heard of guys putting a coating (kinda thick from what I saw) of glue on them, be it epoxy or something else. These guys used epoxy, and it worked fine. Also it takes a good while to come off, although it still did. The heat activated shrink tube works great for hunting purposes, it just doesnt last long! Dont use it for practice sessions, put it on a time or to to make sure nothing changes before hand, but practice on bare metal....then put a set on for hunting season, it works, just a bit or work then again what isnt lol.
http://www.geocities.com/tradbow007/...dventures.html