9mm/.35 cal

k98mike · 09-07-2019, 08:45 AM

If a 9mm is .35 caliber, then why isn't the .380 called the .350? Is .380 just a made up caliber? Is the diameter of a 9mm and a 9mm kurtz the same?

HerrKaiser · 09-07-2019, 10:06 AM

The back of the casing is .38 inches and that’s where the measurement comes from. The case tapers slightly for chambering down to around .355 inches. (the reloaders can probably answer this question with more detail)

mrerick · 09-07-2019, 10:15 AM

The designers and manufacturers of cartridges are the ones that name them. There is little consistency in the way that they are named.

Sometimes they reflect metric measurements of the bullet and case. Sometimes the inch system. Sometimes it's completely unrelated to the bullet diameter (as with .38 Special). I expect that some of the naming is marketing related (the number is larger therefore the cartridge must be "better", etc...)

Some cartridges have multiple names depending on where they are manufactured and sold:

9mm short = 9mm kurz = 9mm corto = 9x19mm = .380 acp...

9mm Parabellum = 9x21 = 9mm Luger....

There are others like this... some have very different dimensions like the 9mm makarov cartridge, which has no relationship to the 9mm Luger cartridge.

You can find the actual specifications that have been standardized by SAAMI at:

https://saami.org/technical-informat...mber-drawings/

Vlim · 09-07-2019, 12:56 PM

9mmK / .380 ACP is 9x17.
9mm Makarov = 9×18.
9mm Para is 9x19.
9mm IMI is 9x21.
9mm Mauser is 9x25.
Etc...

09-07-2019, 08:45 AM	#1
k98mike User Join Date: Mar 2018 Location: Newnan, GA Posts: 141 Thanks: 280 Thanked 48 Times in 30 Posts	9mm/.35 cal If a 9mm is .35 caliber, then why isn't the .380 called the .350? Is .380 just a made up caliber? Is the diameter of a 9mm and a 9mm kurtz the same?

09-07-2019, 10:06 AM	#2
HerrKaiser User Join Date: Feb 2018 Location: South Carolina Posts: 848 Thanks: 784 Thanked 861 Times in 411 Posts	The back of the casing is .38 inches and that’s where the measurement comes from. The case tapers slightly for chambering down to around .355 inches. (the reloaders can probably answer this question with more detail) __________________ -QM Looking for Mauser S/42 toggle train #22

09-07-2019, 10:15 AM	#3
mrerick Super Moderator - Patron LugerForum Life Patron Join Date: Dec 2009 Location: Eastern North Carolina, USA Posts: 3,909 Thanks: 1,374 Thanked 3,110 Times in 1,510 Posts	The designers and manufacturers of cartridges are the ones that name them. There is little consistency in the way that they are named. Sometimes they reflect metric measurements of the bullet and case. Sometimes the inch system. Sometimes it's completely unrelated to the bullet diameter (as with .38 Special). I expect that some of the naming is marketing related (the number is larger therefore the cartridge must be "better", etc...) Some cartridges have multiple names depending on where they are manufactured and sold: 9mm short = 9mm kurz = 9mm corto = 9x19mm = .380 acp... 9mm Parabellum = 9x21 = 9mm Luger.... There are others like this... some have very different dimensions like the 9mm makarov cartridge, which has no relationship to the 9mm Luger cartridge. You can find the actual specifications that have been standardized by SAAMI at: https://saami.org/technical-informat...mber-drawings/ __________________ Igitur si vis pacem, para bellum - - Therefore if you want peace, prepare for war. Last edited by Vlim; 09-07-2019 at 12:53 PM.

09-07-2019, 12:56 PM	#4
Vlim Moderator Lifetime LugerForum Patron Join Date: Oct 2002 Location: Europe Posts: 5,053 Thanks: 1,036 Thanked 3,989 Times in 1,205 Posts	9mmK / .380 ACP is 9x17. 9mm Makarov = 9×18. 9mm Para is 9x19. 9mm IMI is 9x21. 9mm Mauser is 9x25. Etc...