The Elk Can Tell

Technomad is upset at the vast array of cartridges available out there.

He indicates that he nearly bought a box of 9mm Largo for a 9mm Parabellum gun, but a fast thinking gun shop employee caught it in time.

That raises the question, "just how many 9mm rounds are there?"

A fuck-ton. A metric fuck-ton.

9mm Action Express
9mm Largo aka 9x23mm, 9mm Bergmann-Bayard, 9mm Bayard Long
9mm Browning Long
9mm Federal
9mm Glisinti
9mm Luger aka 9mm Parabellum, 9x19mm, 9x19mm NATO
9mm Mauser
9mm Steyr
9mm Ultra 

9mm Winchester Magnum 

9x17mm aka .380 Auto, 9mm Browning, 9mm Corto, 9mm Kurz, 9mm Short, and 9mm Browning Court

9x18mm Makarov
9x21mm
9x25 Dillion
9x56mm Mannlicher
9x57mm Mauser
9x57mmR Mauser
9x63mm
9x70mmR Mauser
9x71mm Peterlongo 

Normally I would say, "Check what's inscribed on your gun," but too often older guns just say 9mm on them.

Spanish guns in particular don't make a distinction between 9mm Largo, 9mm Parabellum and 9mm Browning Long.  They just say 9mm!

That means that if you're going to be buying old pistols, you need to do some research and find out what calibers it was chambered in and double check before buying ammo or going shooting.

It will save you money and could save your life.

But that's just 9mm.

There's a seemingly endless list of cartridges that don't have a real distinction between them except that they don't interchange and what model gun chambered them.

This leads to Uncle Robert on Mom's side eating Christmas dinner with us and Uncle Bob on Dad's side eating with us on Christmas Eve.  As far as the deer can tell, there's not a hair's breadth difference in terminal performance between .30-06 and .280 Remington.  I bought a rifle in .270 Winchester just to stoke the fires of that fight.

There's literally no difference downrange between .30 Remington and .30-30.  The difference is the case.  .30 Remington works in the semi-auto Model 8 and 81.

The deer likely wouldn't be able to tell if it was killed with either of those or .300 Savage.  Or .30-40 or .30-06 or .308 Winchester.

Jeff Cooper used to go after new rounds which duplicated the performance of existing rounds all the time.  He took the position that a bolt gun was a bolt gun and there's no need for new rounds in them that are identical in performance to the older round.

And that's not even the beginning of why there's so many rounds.

Everyone who sits down to make a new cartridge thinks they're breaking new ground or finding an improvement over something that exists.

Don't worry about it.

Buy what you like, make sure you can identify and find the ammo for it.  Go shooting and have fun!

Ideally, you will not need to know about more than five or six cartridges.

Me?  I love to play with all sorts of actions and designs.  That leads to a plethora of different cartridges here in many different kinds of gun.

I have a sorting system and I use it.

I learned the hard way that a box marked .30 Government can mean .30-40 AND .30-06.  Happily, I knew someone with a Krag who was perfectly willing to trade round for round.

Oh, none of this touches on the rounds which can be fired from the same gun despite being different cartridges; like .38 Special and .357 Magnum (and others).