I'm in the process of doing mine right now. In addition to painting it, I also bedded the action and recoil lug and also stiffened the forearm so it wont hit the barrel. I just put the last coat of paint on it, then I'm putting on 2 coats of satin clear. Here's what I did so far:
First I opened up the barrel channel to get the stock farther away from the barrel, and also cut notches down the bottom of the channel to make a place for me to install a pc of steel square 1/4" stock for rigidity.
Next I bedded in the pc of steel using Devcon epoxy. It's a 2 part mix that fully cures in 1-2 hours, but only gives you about 5-6 minutes to work with it so you gotta be fast. The stuff I used dried clear, but it didnt matter cause I was gonna paint it anyway.
With the forearm done I turned to the bedding of the action and recoil lug. I noticed that my front pillar was sunk down in the stock and my action was not making full contact with it, so I sanded it down to the pillar, removed some plastic around the recoil lug area, and then bedded it with the same Devcon. This is really tricky cause if you dont put a release agent on the action it will weld itself to the stock, which aint good
. I used LPS spray as my release agent, which works good. Here is the action setting up in the stock. After about 2 hours it was done.
Next I cleaned everything up and sanded the stock to rough up the plastic. I then applied 1 coat of Rustoleum indoor/outdoor primer, then 2 coats of Krylon Fusion green camo paint( Krylon fusion is made for plastics and sticks very good. I recommend it highly). After that I applied 2 coats of Rustoleum "making it stone" texture paint( it is like a splatter paint the makes it virtually slip free).
It looks blue in the pic due to the flash, but it is really an OD green color with black and white splatter.
Thats it so far. After I clear it I will take some pics in the daylight so you can see the real color, and also a pic of it all back together. All of the paint and supplies I got from my hardware store, but Walmart sells it also.
Good luck on your project.