Plenty of traditional muzzleloaders have been stocked with ash. Is the wood properly dried and ready to be worked or is it recently cut? Do you want to do the work yourself or have someone else do it? If you're wanting a project I recommend going with Custom Rifle Stocks in Aaronsburg, PA.
Like you, I had a piece of wood from a sugar maple on my aunt and uncle's place, a tree we'd all walk by every time we went hunting. An ice storm took it down and I eventually had CRS profile me out a stock set for a Ruger No. 3 project. I'm in the home stretch with it now and its been very satisfying.
