You wouldn't have any pictures of the spray cans would you
Sorry, I was busy trying to take a picture of my camera... I think Krylon webbing is the only spray can product I use anymore, then just when wanting a heavy webbing... But did quite a few before and what the heck its fairly fun to do if you want to mess with it. All the dozens upon dozens of threads here in Hunting Rifles over the years really peaked my interest to get back into stock work...
Here's some CAN pictures LOL...
Usually at the autoparts place they'll have a paint area. Any adhesion promoter that specifies for use on plastic is not going to hurt. I use a brand called Bulldog, generally I have not seen it other than at automotive paint stores. Kinda the same idea as using an etching primer on bare metal, start from the start, get it done right. It sucks bigtime to get it all done up and have your paint job slough off...
But, I bet if you start with Krylon Fusion or another paint that is plastic-specific it'd not be needed to use an adhesion promoter necessarily. The Krylon and Rustoleum "camo colors" flat paints are sure bets for color IME.
If you get screwing around with files and sandpaper etc using a sanding primer (or sandable filler), again that is specific to plastic, is really helpful! This was a big lesson learned. If you just try to hide surface flaws and chit with your color coat it could end up a mess. TOO thick is bad. This way you fill the flaws and do a light sanding to smooth it all up and your color coat will lay down nice and even without having to go TOO heavy. If your surface is good to go - skip this and save time. I can not really tell any 'functional' difference between the rattlecan sanding primers and the 2k urethane automotive sanding primer.... As always I suspect the 2k is greatly superior or it would not exist as such.
Then put down a color. Then maybe some webbing....
And, whatever the reason, with rattlecan use a clearcoat. Anytime I have skipped it I regretted it. Other's experience may vary on this.... BTW: have had zero issues blending Krylon and Rustoleum brands...
Also, this stuff or Krylon's equivalent is a good way to get a little texture. I don't think either are plastic-specific so should use a primer. Read the cans. The first layer on the surface must be for that surface material, from then on paint sticks to paint.... I don't like the looks by itself (of the Multicolor Texture) but had good luck using it under my color base colors. It works ok to hide MINOR surface flaws but it'll go on toooo heavy and it takes days to dry if used heavy. I dicc'd up so many projects trying to put stuff back together tooo soon after rattlecanning... Got a nice tight bedding job? Rattlecanning heavy is a surefire way to dicc-it-up. This stuff will sag too if used too heavy. It dries to a pretty tough finish...
Final thought. What the hell are 2K finishes? My simple understanding: Well, generally they're superior to anything in a rattlecan. Two-part catalyzed coatings will chemically CURE, chemically bonding into a different molecule. Whereas, a one-part paint will simply DRY, the carrier (or solvent or whatever) will evaporate out of it. You add another solvent to it and it'll re-liquefy! 2k stuff doesn't (shouldn't) readily do that. That's why you can get a bit of gasoline on your truck and it'll not rub off your clearcoat. So - if you might have some chemicals around, sweaty hands, blood, piss, or whatever near your rifle, a good professional stock FINISH job may be worth it. Shameless plug. Cheers.