3-IN-ONE oil is a petroleum distillate not mineral oil, and its no different than the stuff we used to get in gun cleaning kits from SEARS or where ever.
For pinpoint lubing of moving parts its fine, but like most oils it will run off or soak into foam or fabric gun cases and leave metal unprotected in high humidity. (My blued guns started rusting in 2 weeks during Hurricane Juan in Louisiana in 1985.)
Also, you don't want to use petroleum based oils on stainless steel guns because it tends to congeal. Vegetable based oils are better for SS hardware.
I can get through a month long duck season with carefully oiling all exposed shotgun metal and running a TICO TOOL through the bore after each hunt, no matter how much wing shooting I do. Shotgun propellants are loaded with graphite which protects the bore and unless there's a mess of melted plastic in the bore (from shot cups/wads-Plastic buildup is a dangerous no no) the barrels won't rust between hunts and there's no reason the break out brushes or solvents. I do carefully and lovingly oil all external metal and wipe off as much as I can get off every hunting day so fingerprints, duck blood or plant sap don't etch the metal.
If I don't fire a rifle during a deer hunt then it's an oil patch in the bore followed by a dry patch after every outing. (again the point is to remove as much oil as you can and the light coating left behind will protect the bore and not build up to eventually pose a dangerous condition or hinder accuracy) and I wipe down all accessible metal surfaces.
IF I SHOOT THE RIFLE once and hunt the next day or so that's fine because it will count as the "oil shot", meaning the next few rounds will be expected to shoot to point of aim once the oil has been "shot out". (assuming dry weather of course-rain changes everything and I take no chances)
But, if the hunts are broken up on separate weekends and I fire even one round the rifle will get cleaned. I can't stand to rack a gun for more than a few days knowing that the bore could be under attack or that copper fouling may reduce the accuracy next time out.
With shotguns the priority is wiping external surfaces (I like using silicone cloths for this) and making sure no moisture is in the bore (including in the threads of removable chokes) or inside the receiver. With rifles the priority is the bore and all other metal that could rust from moisture or fingerprints. It doesn't benefit me to work myself stoopid cleaning every night or to go in the field with a rifle stinking of solvent or oil products.
Generally speaking some of us probably over-cleaned our shootin' irons, especially when we were younger. It's been argued that we wore out more bores with raspy aluminum ramrods and bore brushes than we ever did with live fire, and with .22s it isn't hard to damage the crown that way.
Now days I use common sense and err on the side of caution and I still don't have to clean mah iron as much as I used to believe to keep them rust free and in good working order.
Like all things you must have your priorities straight, so, if you accidentally drive your pickup into the lake remember to hand the rifle up to a buddy then swim back to collect the little woman. (she won't rust)
And, if that's the worst that peeps can say about me, then it probably won't keep me out of heaven.