This should really be moved to George Stringer's forum, but here we go...
Disassemble the firearm and bead blast all surfaces you want refinished. Do not touch blasted surfaces as you want to keep them free of oil.
I like putting the metal into a solution of hot water (warms it up) and also to ensure that it's degreased. For small parts, I put them into a stainless steel teaball (I have a large 2" tall one which is about 1 1/2" wide). This keeps you from struggling to pick up small parts which may drop out from your basket.
Next, in a stainless steel pot or tank, mix your parkerizing solution (available from numerous gunsmith suppliers) per instructions with distilled water (don't want additional chemicals from tap water to mess up your finish. If you're well/spring water is good, you can use that too). This is brought up to about 185-200 (the exact temperature escapes me - so read the instructions that comes with the parkerizing solution). Let the metal sit in the hot solution for 3-5 minutes.
Pull out and place into a separate neturalizing solution to stop the process. I also like to keep this hot as it promotes drying.
Dry and oil. Being old fashion, I allow it to cure by sitting for 24 hours.
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