Any of the major brands will do a good job. The best system is Outer's Foul Out.
A very mild acidic cleaner <><><> For light rust, soak in penetrating oil (I like KROIL, but PB Blaster is good also) overnight. Rub with clean coarse cloth, such as burlap. Deeper rust may require stronger methods. Try a copper pot scrubber, such as a Chore Boy pad, toether with the oil. INSIDE the barrel, use a good bore cleaner, and a bronze bore brush.
salt
Best left to a gunsmith.
Best left to a qualified gun smith.
If there is no maker's name on the rifle, it is likely a (former) military rifle. Without a full description of the rifle, and ALL markings on the rifle, there is no way that we can answer your question. Your best bet would be to take to rifle to a local gun dealer. Sorry-
Best source would be old gun catalogs and magazines.
We called ours Winchester. He was thin as a rifle barrel when we got him...
Sure. It is best if the copper is clean of grease or oil, first. Sometimes the baking soda is mixed with vinegar instead of water, but either way it is a good cleaner.
I have no mention of Kreige in my references as a gun manufacturer. Kreiger is a barrel maker. Please repost with a full description of your rifle, all markings, and we will do ou best to get you an answer.
Vinegar is a great cleaner for copper. The smell will go away once it is dried so do not worry about your home smelling like vinegar. There are also polishes one can buy for copper.
The best BB rifle is the one you can afford. But let me give you more detail.BB rifles are not as accurate as Pellet rifles. Because BB rifles use a smooth bore barrel. Pellet rifles use a rifled bore barrel. BB's don't spin when shot out of the barrel, they tumble. Pellets spin as they leave the barrel. This makes them more accurate.When you say "BEST" do you mean accurate, quality or power. What is your definition of "best".If this is your first rifle then I suggest a Daisy red ryder. Learn to use it properly, then move up to other rifles.See the link below for various BB/Pellet rifles and select one that you like. I suggest the Crosman M4-177. but look at them al first
BB rifles and BB guns are neither accurate or powerful. Basically because of the design of the barrel. Most BB guns use a smooth bore barrel. Where as pellet rifles use a rifled bore barrel. It has grooves that make the pellet spin and fly straighter. BB's tumble when fired out of the barrel. BB guns can injure you but never attain the accuracy, power or speed of a pellet rifle. The best BB rifle I know of (NOT Pellet only rifle) is the Daisy 880. It is capable of firing both BB and single shot Pellets.