Just a thought about steel wool.
Yes, the stuff you buy at the store has oils and waxes on it to prevent it becoming a pile of rust on the shelf.
These waxes can raise havoc with blueing (and hot browning like Plum Brown) by contaminating the surface and preventing the very rust you want to form.
To degrease/dewax steel wool for blueing, I've tried Acetone, Lacqure thinner, MEK, Brake solvent.... and none of them work good enough.
I have found the very best method is to soak the pad(s) in a 50/50 solution of water and Muratic (Hydrochloric) acid for 3-5 minutes and rinse with plain water. You know you removed the oil/wax because the pads will start to rust.
This is undoubtly a case of over kill for steel wool which is going to be used on wood though.
A thought about using steel wool on wood:
The small fibers which break off of the steel wool pad will contaminate your stocks surface.
Perhaps when dealing with a dark wood like Walnut, it doesn't matter but I guarantee if your working with a blond wood like Maple, and you intend to use any acid or water based stain you will regret having used it.
The small fibers will rust as soon as the acid or water base stain hits them, leaving tens of thousands of red freckles all over the wood. These freckles will not bleach out, or rub off. The only way I've found to remove them is to resand the stock and start over with the whiskering.
If you use an oil base stain, or no stain at all, the fibers will not be a problem.
As I never use a oil base stain on my guns, and this freckling has occured on one of my guns in the past, I never use steel wool on a Maple stock. :m2c: