Is there a reason why some shotgun shells have different colors

What are the different types of shotgun shells?

Choosing the Best Shotgun Shells

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Understanding your shotshells - Sporting Shooters' Association of

What was the old blue shotgun shell called? - Quora

Why do shotguns have different looking shells than rifles? - Quora

Shotshell Color Coding

Throwback Thursday: Understanding Shotgun Shells 101 - The Shooter's Log

Shotgun Shells Explained - Types Of Ammo (Birdshot, Buckshot, Slugs)