Are 38 S&W vs 38 Special Ammo interchangeable?

The .38 Special and the .38 Smith and Wesson are not interchangeable. .38 Smith and Wesson is larger in diameter than the .38 Special.

Ammo: What You Want vs. What You Have - The Shooter's Log

The .38 Caliber Handloader Magazine

38 Special vs 9mm - What Does Each Caliber Offer?

38 Special vs 9mm - What Does Each Caliber Offer?

Cartridge of the Century: A History of the 38 Special

S&W .38 M&P Victory Revolver - Shooting Times

38 S&W vs. 38 Special

GUNS Magazine The “Other” .38 - GUNS Magazine

38 S&W vs. 38 Special - What's the Difference?