Luger ID .30 cal or 9mm

[Josafoot]

Originally Posted by ithacaartist

Either .30 Luger or 7.65 Parabellum. None of the others is an accurate name for this ammo.

We used to recommend the "pencil test" for caliber. A standard pencil will plunk right down to the bolt face when dropped into a 9 mm barrel. In a .30 Luger barrel, it will be snug or a no-go.

I tried a Pencil and it was tight but I could push it through. Not a plunk.

I also tried a .303 British round and that went most of the way but got stuck where the bullet is at its widest. To be fair, I was not going to push it any further.