What do I use to measure ammo length?

[BabySherman]

I'm trying to find out the length of ammo that can be used in a 357 evanix Max's mag.

Do I use standard or mm? Thank you. 

 

[jbravo103]

measure with a digital calipers. most can measure both mm and SAE, or convert units manually. Yo!

 

[corny]

StrelokPro (iOS app) has most ammo preloaded including length