has anyone ever used the back on finish, I know you can get it from brownells. does chip easy? what do you have to do? other than removed all plastic?

Are you talking about the Brownell's Moly Coat? If so I had ran into a bad batch about two years ago, did two FAL's and the finish flaked off. I sent the cans back for testing to Brownell's and went with Gunkote instead which worked fine. The key though is the prep work, you have to use aluminum oxide to blast and not silica bead. Also get some TCE to properly strip any oils or residue off the blasted parts before applying the KG product. Also temperature does affect the outcome, use only in a dry room temp environment for applying any product and give it a while to cure before the final baking in the oven. As many here will tell you- the stuff stinks up the whole house when baking.  If you are doing this on a budget then I would get one of those plastic blasting heads from Harbor Freight, they also sell the aluminum oxide.

If you use GunKote in the house oven make damn sure the wife ain't home and will not be home for a while.  Open as many windows in the area as you can and put a fan in the window to "suck" out the fumes.  That stuff baking has a very horrible chemical smell and you may get a visit from the LEO's when your neighbors call in a drug lab next door!  It's bad man, real bad.  I will never do that again it smells so bad.  I use Brownell's AH II now.  GunKote is tougher but it will scratch too and when it does it leaves a lighter color where the scratch is.  AH II scratches too but all you have to do there is mask off everything else around the scratch and touch it up.  Can't do that with GunKote.    

I think some people confuse Brownell's Moly Coat with Norrell's MolyResin.  They are not the same product.  MolyResin is great stuff.  Also, while I have never baked GunKote before, I have baked several times with MolyResin.  Yes, there is an order but it's not what I would call bad and it doesn't smoke like engine paints do in the oven.

do have to bead it? I was wondering why can't you just use a denatured alcohol and a primer?

You don't want to use beads, you want to sandblast it.  Beads can leave the metal too smooth.  No, you don't want to use a primer other than some sort of park finish.  MolyResin and GunKote are not paints they bond with the metal surface when you bake them.

thanks for the information, it really helped.