intermediate caliber

[PegLeg45]

How come for the first 75 years of smokeless powder did all military's settle on a round rifle caliber between 6.5 and 7.92 ?

I guess they were still in the "bigger bullet to compensate for slower velocity" mindset...until they finally figured out that speed kills almost as good if the bullet is made right. 

Now I guess everyone is still trying to find that happy medium magic cartridge. 

[les snyder]

look for your 6.5 to be a 6.5x51 or longer case to make use of the superior ballistic coefficient of the 6.5 bullets...for 1500m targets

[tombogan03884]

Over on Forgotten Weapons some one wondered why second rate powers , Japan, Italy, Switzerland, Austria-Hungary , etc chose 6.5 variants while the major players such as England, Russia, Germany, and France went with 7.62 to 8 mm range. Ian's answer was that he thought it might just be coincidence.
I notice though that the larger bore countries were all more or less colonial powers habitually fighting savages while the 6.5 countries, with the exception of Italy, were only fighting each other.

[les snyder]

longer range shooting... across the valley from one side of the mountain to the next

[TAB]

I like the 6.8 spc personally.    the only thing I like about 556 is you can carry a lot of it.    still if I am in the sand box, I want more.   not so much for the longer range, but so I know if I hit them, they go down.  there is an ~800 ft lbs difference betweent he 556 and the 762

[Sponsor]

[Big Frank]

"So how does a varmint round, a high power .22 qualify as an "intermediate" caliber ?" Simple. It's intermediate in power between pistol cartridges like .45 ACP and main battle rifle cartridges like 7.62x51mm.

[tombogan03884]

Frank, the whole point of this thread is that it ISN'T half way between.45 and a battle rifle round. 5.56/.223 isn't even in the same class as a real military round.

[Big Frank]

Frank, the whole point of this thread is that it ISN'T half way between.45 and a battle rifle round. 5.56/.223 isn't even in the same class as a real military round.

You're right. It's MORE THAN halfway between them. The last time I looked up the muzzle energy of the 3 rounds, the 5.56x45mm was over 3 times the power of the .45 and about half the power of the 7.62mm. If it's not, then what has changed? Perhaps I should have said the 5.56x45mm is intermediate in power between a .22 rimfire rifle and a .30-06.

[les snyder]

don't overlook the effect that Army (Marine) doctrine plays in the selection of military small arms...if non symmetrical urban warfare against dismounted troops is the most likely opposition, a MK18's 10.3" or M4's 14.5" barrel makes a lot of sense ...

[Rastus]

Intermediate caliber, isn't that something like 75 to 150 kilitons?