Spray-on oven cleaner (heavy duty or otherwise) works very well to darken cherry. The amount of color change is dependent on how long you let the lye sit on the stock. I sprayed a test sample, then wiped it off at 30 second intervals down the board to see the color differences. If left on too long the stock can become dark brown and almost unrecognizable as cherry (except 200 year old stuff). Rinse off with water, then neutralize with vinegar. If using an oil finish, you want to be sure that you've removed the lye entirely, otherwise you'll end up making soap on/in the stock. Every cherry gun I've finished had the lye treatment - as with aquafortis, every result will be slightly different. IMO it looks a lot more authentic than diluted LMF cherry washed over the wood.
Best,
-Eric