I know this is not really a gunsmithing issue, but I figured someone here could help me out...My new bird and trout knife has a stacked leather disk handle that has some dry, rough spots-what is the best way to smooth them out and to treat the leather? Thanks!
You could try a light application of Neatsfoot Oil, available at leather shops (Tandy, etc). It will darken the leather a bit, but will restore any dry spots, and protect it from moisture. This is what I use when making knife sheaths.
Go slowly with some fine grit sandpaper (220-320) on the rough spots, then apply some sort of leather conditioner. Neatsfoot oil is good stuff but will turn the leather almost black. If your worried about the color you might look into some other stuff.
As above, smooth out rough areas with sandpaper. Teat with whatever leather dressing you like.
Then apply a light coat of Thompson's Wter Seal. Although made for wood and canvas, light applications will waterproof the leather without making it greasy.
I've used this on Ka-bar knives used by divers. It prevents the leather from rotting or getting water soaked, either of which will destroy the handle.