Fluid Film looks a lot more appropriate for my intended use than WD-40...Try fluid film. Lasts much longer than WD-40 for anti-corrosion.
That said, I like to use a little WD-40 inside the gun barrel after I clean it, then run a few patches to dry it up. Keeps the moisture out of your barrel, and your gun will shoot just fine with the first shot. Everything has its purpose!
I've also found that the Hornady One-Shot is both very easy to use and works well for cleaning the barrel. I spent a lot less time cleaning barrels this year, and they have been shooting just great! I generally just spray a little in the barrel, run a few patches, then spray the WD-40 in the barrel and run a few patches. Much easier than what I used to do.
The only time I use WD-40 on guns is as a solvent to flush debris out of revolver actions (side plate off) or to dry out a gun that has gotten wet. I still use Hoppe's solvent for cleaning smokeless guns... though I've got other stuff for removing wad crude and JB and brass screens for removing leading in handguns. Sometimes I use Breakfree. For black powder I use Ballistol... this was recommended to me by a former co-worker and longest serving master of the gunsmith shop at Colonial Williamsburg. It almost makes cleaning the long rifle fun it works so well! I use either straight Hoppe's gun oil or the same with some liquid silicone added for the exterior and bore... though if it's hunting season I leave the bore damp with either Hoppe's or Breakfree and then wipe it out with dry patches to leave the bore rather dry. This is where I landed after a half century plus of gun cleaning and it has worked for me. Note that gun grease is used for lubing things like SxS and OU bearing surfaces and some bearing surfaces in my target pistols... I lube very sparingly in very cold weather.