Savage 330- rust blued, or hot blued??

Greetings, This is my first post, and probably won`t be my last. yesterday, I traded for a Savage 330, 20 ga. It is mechanically perfect, but the factory bluing is missing in spots, and there is a little pitting under the forearm. What I want to know is were these shotguns rust blued or hot blued. The solder at the end of the barrels, seems to be soft, which leans me toward rust bluing. The color on the barrels is more black than blue. I have Mark Lee rust blue solution, but don`t know if that would be {right}. I`m also looking for a take down, gunsmithing guide. What do you gentlemen suggest? Thank You..........Art.

If the solder is soft, then you have the right idea, rust blue. Don't pay any attention to the color of the existing blue. You might take a look at Laurel Mountain Forge Barrel Brown and Degreaser( Brownells). It is much easier to use than the traditional rust blues since it contains a detergent.
You can bare hand the parts when applying the solution and during carding as the detergent cuts right through fingerprints and skin oil.
I know it says "Barrel Brown", but it does a beautiful rust blue when used in the traditional rust blue process.

RWO