You don't wanna "spray on" nuthin. :
You want hand rubbed,,it's a gun stock. Most hand rubbed finish means you use one finger, and apply a few drops at a time. This process will only take a few or up too 10 days dependant on level of finish you desire. This IS a place where many screw up badly, because they want to shoot it NOW!!
1st is to protect the wood from the elements, and that means the moisture in the summer air and the dryness of winter.
Laural Mountain Forge, Permalyn sealer,,this stuff soaks in deep and dries fast (hours), cover every inch inside and out, you brush this on with a $1 art brush from the hobby shop.
You want gloss? Now comes the
rubbed part,,
Bichwood Casy Tru-Oil; Has been mentioned, very easy, some what suseptable to moisture. Put your gun in the rack on a dewwy morning and you'll see some color change, it gets cloudy for a little while and can develop tiny hair line cracks, most folks won't see this.
Spar varnish; This stuff has been use on marine/boat applications for centuries. Go to a fancy bar that has alot of wood,,that stuff that looks like glass? That's Spar.
Tung Oil; Made from the Tung tree, used for about 4000yrs by the chinese and then the rest of the world since trade began. A single coat dries in 10-12 hours.
Boiled Linseed oil; Gotta mention it, most don't like to use this much any more because a single coat can take day's to dry, this is the stuff you see on antique firearms in the museums.
All of the above can continue to be applied for years, if your stock takes a few hit's or dings, it's all about a light sanding, (300-400 grit ??, I don't know your level?) and just rub on another coat.
Good luck, I urge patience,,Take a few day's here and you can have something you can keep and hand down for generations, or if sold, have an increased value because of the care taken.
Personally, I use the Spar for idiots, If I know it's going hunting, and/or the guy's aren't big on care. I'll use the spar for it's tuffness, I dull it down with steel wool. Tru-Oil gets used for re-furb jobs, it's fast, covers well and the common guy is happy with it.
For the Range Roosters or deep curl fancy stuff I've used BLO but that's for folks that will give continued care. The last few and personal stuff have been Tung Oil, just as easy to use as BLO and dries a bit faster.