Here in Massachusetts we can only have preban magazines that hold over 10 rounds. That is made before September of 94. So I bought some preban mags, most are from 87. As you can imagine lots of wear and tear in 29 years. Tried my hand at refinishing them to look a bit better.
1) Soak and wash in warm water with small amount of Borax powder. Rinse well.
2) Put in toaster oven and heat at 250 for 30 minutes to remove any and all traces of moisture.
3) Spray each side with several light layers of CRC dry moly. Spray one side and let dry for 15 minutes, then repeat other side.
4) Place in toaster oven at 300 to 315 degrees and bake for one hour. I confirmed temperature with infrared heat gun.
5) Let cool with door shut then remove and wipe powder residue with microfiber cloth. It has many facets in the cloth but is not abrasive.
6) Install new generation 3 magpul followers. Install ranger plates. (New springs if needed)
There will be slight in-perfections due to age, scuff marks, wear and tear. Results.