Oh, deary dear... Here's some knowledge that ain't burny hot, but needs to go around.
My Unca Harry came home with a break action .45 Webley he got from a Brit. He shot up the ammo he'd brought back with the pistol, and went into a hardware store to get some more. Bought a box of 50, and was gumping with the hardware guy who was a vet also.
Unca Harry mentioned his Webley. The hardware guy did a double-take, and asked if that was what the .45 ammo was for. "Yup" sez Unca Harry.
"That'll blow your hand off. The Limeys made wimpy .45 rounds. That gun will not take American .45 cal pressures even though the bullets fit just fine in it."
So I got to play with the empty Webley every now and then. It was never fired in the US with US ammo.
View attachment 340452