Because it is heavy (retains energy for greater distance), soft (fits itself to the barrel of the gun) and cheap.
Copper, Lead
Bullets and ammunitions
Lead
Blue bullets are bullets are high quality Polymer Coated Lead Bullets.
Yes, may people use lead bullets for a variety of purposes.
A better question would be which do NOT have lead. A small percentage of rifle and handgun bullets are solid copper, bismuth, or some non-lead metal. Shotshells used for waterfowl are loaded with non-lead shot- steel, bismuth, or iron/tungsten alloys. But MOST bullets are still lead. It may be covered by a gilding metal jacket, but it is there.
Yes. Lead bullets do not wear out the rifling inside the barrel as fast as steel bullets. Still, many people use steel-jacketed bullets . . .
Bullets
Bullets can be made from many materials including wood, steel brass, copper, lead, tungsten, bronze, plastic, etc.
they use (Lead) because it has a low melting point and easy to mold and cool. they also use it because it is light enough to be shot farther but it also has enough weight so the wind wont affect its accuracy as much Lead is used only in cheap bullets. Better bullets are an alloy of lead and antimony. Many common lead bullets have a copper or steel 'jacket' -Most accurate rifle bullets are a bronze-nickel steel mix, or a copper alloy.
Usually they aren't. Lead, or lead in a copper shell (a "jacket") is the most common choice for bullets. Bullets CAN be made of mild steel, usually also copper jacketed, and it's usually done because of concerns about the lead from the bullets causing pollution. Mild steel is one of the less expensive replacement options for lead in bullets.
The same metals used in long guns: A lead core with a copper jacket. Due to concerns about lead polluting the environment, some bullets now contain Bismuth or other metal.