Why are bullets made up of brass, not aluminum?

There are many benefits to using brass bullets instead of aluminum ones when shooting firearms — including improved accuracy and performance

How do bullets work? - Explain that Stuff

Why aren't ammo casings made out of aluminium instead of brass (brass which is way heavier than Al)? - Quora

Exploring the Reasons Behind Aluminum's Easier Oxidation: The Science of Aluminum Oxide

Aluminum VS Brass Ammo: Head To Head Comparison

Decoding Ammunition Boxes

Steel VS Brass Ammo - Wideners Shooting, Hunting & Gun Blog

The Great American Ammunition Conspiracy - The American Prospect

Buffalo Bore Hardcast Ammo: Most Powerful Bullets - Handguns

Can any metal be used to make a bullet? - Quora

A New Method of DNA Testing Could Solve More Shootings

Beginner's Guide to Pistol Ammo - Lucky Gunner Lounge

Bullets First Manufacturing, Bullets

Goodbye, Brass? An NRA Shooting Sports Journal

Monolithic bullet - Wikipedia