>>64434516
>What actually is the process for spray painting a gun?
Depends on how good you want it to look.
If it isn't stainless you can parkerize it first to give the bake on finish extra adhesion. Prep work involves careful removal of material until it has a near mirror finish and then ruining the mirror finish with sandblasting.
If you aren't clever enough to articulate what you want, you spray the cheapest rattle can labeled "black" on it until it's "black".