My father and I put some sort of camo tape stuff on our .22s for extra camo when sneaking up on crows in our corn fields, and after years we came to regret it. The stuff melted the varnish on his gun and on both of our guns the stuff sorta melted and got all sticky and gross. Can't remember the brand, but I'd recommend more of a hockey tape or cloth thing as this was similar to a medical wrap. Where I play camo isn't very important as you can just lie down and hide under branches, ferns, and grass, and most of the people have the sight of a cave organism if you're wearing a color vaguely similar to your surroundings. Depends on where you are tho, gun camo may be important.
Also check out the Novritsch skins, they look pretty good.