[Mericet]

Not sure why that happened, but another option for you is to strip the gun, sandblast (not beads) and then Cerakote. The blasting media will eat out any rust. If you buy a small starter kit of Cerakote, it will include detailed instruction on how to use it but I think their website has all of that too. We do this for a lot of customers that have water/rust damage to their guns.

If you want to keep it more original you can save some money by doing the draw filing, sanding and polishing before you send it to someone that can parkerize it.