[moovova]

"Well, .38 and 9mm are larger caliber than say, .223."

Guess I'll stick with .223 since it's only 3/1000's of an inch larger in diameter than a .22 LR. That's not much difference at all.

☺

[mountainlion]

Guess I'll stick with .223 since it's only 3/1000’s of an inch larger in diameter than a .22 LR. ....

Actually they are the same size. You can shoot 22s in the same barrel with an adapter.

[CurlyDave]

...Guess I'll stick with .223 since it's only 3/1000's of an inch larger in diameter than a .22 LR. That's not much difference at all.

The bullet diameter is actually exactly the same as a .223.

There is a long history of how cartridges came to be named, but all .22x cartridges once started out as a 5.5 mm hole drilled in a barrel. In the original scheme of things, the grooves were then cut into the barrel, so a slightly larger bullet was required to completely seal the barrel.

These days there are many methods of producing a rifled barrel, some of which do not cut any grooves at all. But, the cartridge names and bullet sizes are still usually based on the original ways of doing things.

[Axenolith]

No it’s not, it’s an order of magnitude larger, .223 vs .22, see there’s 3 digits in the .223 as opposed to the 2 in .22... /libtardian maths

[IndispensableDestiny]

.223 Remington is .224 inches in diameter.
.22 LR is .223 inches in diameter, but can be found up to .225.
.22 Hornet is .224 inches, except for the old Hornet, which was .223
.22 WMR is .224