Getting ready to cut 80% lowers for some upcoming builds and wondering what people are using to finish the inside of the receivers after they have been cut?  All of the receivers are anodized on the outside.

Most just leave it as is.

I degreased mine and masked off the top and around the pocket. also mask the bottom around the trigger cut out enough to spray the edges of the cutout. and use matte black aluma hyde II to paint the pocket. It doesn't hold up in the pin and selector holes for me, so I don't try to paint them with it. Stuff is thick if sprayed too heavy,

https://noxton.com/glow-paint-termo_en.html

I masked off the outside and sprayed the pocket with a light coat of VHT Epoxy Satin Black, because that's what I had on hand. Just enough to cover. Then after it dried I baked it in the oven at 200 for half an hour (even though that's not what the instructions call for). It has held up very well for several years now.

I painted a lower or two with that during the Aluma hyde II draught. Was surprised how different the two epoxy paints seemed to be. I sanded it off two lowers I used it on because it seemed soft to me. It sanded off like a very fine powder. I didn't think the two paints were anywhere near similar. Both even smelled different to me when they were curing out.

This, the oils will give it all the protection it needs.

I agree the VHT Epoxy wouldn't be good on the outside of a lower. In fact I tried it on a barrel and didn't like it. It came right off in no time, even after the aforementioned baking, with a little solvent and steel wool.

Has anyone used this Rust-Oleum® HIGH HEAT ceramic paint? It seems like a poor mans alternative to Ceracoat. I only plan to use it to cover the bare exposed  aluminum. My concern is the baking temps. 250, then 400, then 600F.


https://www.rustoleum.com/product-catalog/consumer-brands/auto/specialty-paints/high-heat

Specs/instructions: https://www.rustoleum.com/-/media/41F80FD66E694423A47DB1886DCD6F57.ashx

Sorry, repeat post

Jrpett I’m a little late replying but no, I have not used it but I would offer my thoughts. I’m afraid of the 600 degrees curing temperature. If you read about the heat treating of the two common aluminum alloys it’s like this; 980F for one hour, quench in water. Then one of the following; one hour at 400F, five hours at 350F or 8 hours at 325F.

So, the curing of the paint as called for in the instructions is easily within the temperature range of the heat treating of both alloys. I have no idea what effect, if any, the curing temps will have on the aluminum but I am not willing to find out! My guess is it will not have a negative effect but then again, I don’t know. I did buy a can of VHT engine enamel mainly out or curiosity. It does call for a heat cure but at a lower temperature. I intended to paint some gun parts with it but so far have not. I think one day I’ll prep and paint a scrap piece of metal and then torture test it.

At this time I think a finish specifically intended for firearms is the safest way to go. I have been using Norrell’s Moly Resin with very good results.

A quick update. I tried this paint. I was concerned with the 600F curing temp, so I only went as far as the second 400F cure. It appeared to be good. I normally clean my AR type firearms with chlorinated brake cleaner, so as a test, I took a Q-tip with some of it on there, swiped it across the finish, and it removed it. I also tried with some acetone, and the same results. Maybe it's because that it really did need the 600F cure to do it, but as of now, I can't recommend using this. I normally use Molyresin, but mine is over 10 years old and didn't want to use it not knowing if it was still good. My past results with Molyresin have been great using those two solvents/chemicals, it's very resistant to them. Next time I'll use Molyresin.

Thanks for the update.
I have a scope to do. I will either try KG Gun Kote with the low temp additive, or Duracoat. So I don't have to roast the scope in an oven :)