Neither copper coated or jmp are commonly used anymore. FMJ means "full metal jacket" and is found in either rifle or handgun ammunition. Typically also referred to as "ball ammo."
Long ago lead bullets were given a very thin plating of copper and called "copper coated" Today several companies (Speer and Rainier) offer plated bullets where copper is plated onto a lead core. This is how Gold Dots are made and is a very good way to make bullets that can be less expensive that regular jackets.
JMP must be referring to the really old jacketed metal penetrating where a lead bullet had a copper or jacket metal cap- these were in the very early .357 Magnum loads, but to my knowledge there's nothing exactly like that today.
tell us where you got the nomenclature...
