I really like to powder coat for rifle bullets, high velocity handgun, or suppressor use.
It does take a little more time but well worth it.
I got white powder from harbor frieght. It works great for shake and bake.
The powders for sale on the cast boolits forum should only require one coat. Other powders can be found that only require one coat, but you might have to do some testing of your own
The bullet in the attached (I realize it has a flaw), only has one coat. This was the Gloss Blue from The Powder Coat Store. It was applied using the dry tumble method; some bullets and powder in a #5 plastic container, shaken and swirled for about a minute.
I also dry tumble mine in a plastic container with nothing in it except powder and bullets. I pour out the smaller container into a wire basket that has been commercially powder coated. I swirl them around a bit thinning the powder, pour them into a clean wire basket that I bake them in. I don't stand them up and they rarely ever stick to the basket nor eachother. This method saves a ton of time and yields excellent results.