.312 is far closer to .31 than .32, and .309 is far closer to .31 than .30, why is the first considered .32 and the second considered .30?
it isn;t necessarily the size of the bullet in the name of the cartridge. sometimes its bullet diameter, sometimes it is bore diameter in the lands or grooves, sometimes its case mouth diameter,
>>65101796Which part of .30 luger is less than .309 in diameter to be considered remotely .30?
>>65101792Completely nonsensical nomenclature. It's why 38 special shoots a .355 caliber projectile and many 44 caliber cap and ball revolvers use .454 caliber balls. I've long since learned to not question it because you'll never get an answer
>>65101807The diameter of the lands in the bore.
>>65101831NATO tried at least
>>65101832What other calibers are named by their lands diameter
>>65101838.300 Blackout, .300 Winmag, .50 BMG, and most metric cartridge names (5.7x28 is a notable exception)
>>65101796And sometimes none of these and it's just marketing.
>>65101838.300 WM and .300 chimpout have the same bullet diameter as .308. Meanwhile, .22, .220, .221, .222, and .223 all shoot .224 bullets.
>.44 Magnum>.429" bullet
>>65101792Where to measure is still disputed today, IMO half way between the lands and groves of the barrel is the way to go because it'll give you an average diameter after firing.
