no they are not they're made of lead with or without a copper although if you covered the copper jacket with powdered zinc that is in a heated solution of sodium hydroxide it will turn the jacket silver and to turn it gold or "brass" you put it under a flame
Bullets can be made from many materials including wood, steel brass, copper, lead, tungsten, bronze, plastic, etc.
Most are made from one or more metals, including lead, lead covered in a brass alloy, copper, etc. A few bullets are made of a hardened steel with a brass covering, and a few from plastic.
The same thing 9mm bullets are made of, and 7.62x39 bullets, and... well, bullets in general. The case can either be brass or steel. The projectile will primarily be lead. It may have some other type of metal inserted into it, and may or may not be jacketed with copper.
Most are made from one or more metals, including lead, lead covered in a brass alloy, copper, etc. A few bullets are made of a hardened steel with a brass covering, and a few from plastic.
On a B17 bomber the spent shell casings (brass) fell on the floor. Everything was scarce and rationed during WWII so I assume the brass was reused.
Copper/brass: Used for bullets and fuses for every bomb and artillery shell (includes naval guns).
The diameter of the the two bullets are just about the same, but the length of the brass case which holds the bullets are slightly different. The Makarov's case is 18mm long, while the Luger's (Parabellum) case is 19mm long.
Oh, dude, coffee powder in bullets? That's a new one! No, coffee powder is not used in making bullets. Bullets are typically made of materials like lead, copper, and sometimes steel, not your morning pick-me-up. So, you can keep sipping your coffee without worrying about accidentally loading your mug into a gun.
There's no reason you wouldn't be able to, although you might not be advised to mix brass cased and lacquer coated steel cased ammo together.
I think most bullets have always been made, principally, of lead. Lead is soft, heavy & easy to mould or cast. In the times of Musketry bullets were spherical, rifling improved their ballistic qualities and they became pointed cylindrical in shape. Nowadays they are coated in copper, but lead is still their principal metal.
Anything the colonists could melt into balls. When possible, lead, but also iron, copper, brass, and even pewter from the family silverware.
Blue bullets are bullets are high quality Polymer Coated Lead Bullets.