Gun Kote is a decent coating for guns. I did a Mossberg 500, my SKS, and my Ruger 22 pistol in OD green.
I did my PSG-1 with black Gun Kote.
This stuff is pretty much impervious to solvents, including really aggressive solvents like Butch's Bore Shine.
But as stated, the surface needs to be prepped correctly, such as bead blasting. Then you have to pre-heat the part to about 120 degrees, either by setting it in the sun, or in an oven, before applying the Gun Kote.
Once applied, you bake it in an oven at about 300-350 degrees (I forget the exact temp) for the length of time specified.
And on the note of home defense shotguns, I've been looking at one of those new AR-15-type shotguns, I forget who makes it, but I saw one in Shotgun News a while back. Has anyone shot one of these, or own one? If so, what's your impression of it?
On a final note, I'd REALLY like to have a "Master Key" on my AR-15. Basically a master key is kinda like an M-203, except, instead of a 40mm grenade launcher, it's a 12 ga shotgun, mounted under the barrel of the AR-15/M-16.
But I think a master key is classified as an "AOW"...which means dealing with a mountain of paperwork, and the jackboot thugs of the ATF. I have friends in LE, such as DNR and DHEC officers, and I respect the job that they and other LE officers do. But as far as the ATF, I have nothing but contempt for them, and their storm-trooper/gestapo mentality. And from what I understand, if you have a permit for a class 3 or an AOW, it gives the ATF the right to come to your house any time of day or night without a warrant and they can demand to see the firearm and the paperwork. No, thanks...I'll retain my 4th amendment rights. So, unless they do away with the 1934 NFA laws, I'll never own any suppressors, full auto, or anything else where I have to surrender any more rights.