[thackney]

Not remotely the same.

Are substituting cartridge for caliber?

[I cannot think of a name]

“Are substituting cartridge for caliber? “

Not sure what your question is. .38 caliber refers to a predominately revolver cartridge, .380 refers to a semi-auto cartridge. Neither is .38 diamter (.38 = .358”, .380 = .355”)