A History of Military Rifle Calibers: The Infantry Magnums, 1902-1914

The paradigm was established by the 1870s: Future infantry combat would focus on a combination of entrenchment, and long-range concentrated fire from well-drilled units to defeat the enemy beyond his own effective range. The arms race for a smaller-caliber, lighter-weight cartridge accelerated, but it was the Americans and the British that would discover a need for an even higher performance round that could outmatch any fielded by their enemies. Two key conflicts were the Second Boer War, fought between the British Empire on one side and the Transvaal Republic and the Orange Free State on the other, and the Spanish-American War, fought by the United States versus the Kingdom of Spain, most importantly in Cuba and the Philippines. These two conflicts shared one common feature: The opposing sides of each were chiefly armed with advanced quick-loading 7x57mm caliber Mauser rifles, firing high-sectional density 173gr round-nosed bullets at a nearly 350 ft/s muzzle velocity advantage versus the .303 and .30 caliber rounds fired by the British and Americans.


.30-40 Krag M1898, .30 M1903 Springfield, .30 M1906 Springfield


Although the Spanish and Boers lost the conflict, they and their Mauser rifles made a huge impression on their foes. Both the British and Americans set out to develop advanced high-velocity rifle cartridges to replace their extant .30 caliber rounds. The Americans would begin development soon after the conclusion of the Spanish-American War of what became the .30-03 Springfield, a rimless, high-velocity .30 caliber round firing a 220 grain bullet at 2,300 ft/s, equaling the velocity of the long 7mm Mausers, but from the shorter 24″ barrel of the new M1903 rifle. The British would begin a program for a .256 (6.5mm) high velocity rifle, but would eventually create a .276 (7mm) caliber high velocity round that nearly reached adoption, development ended with the beginning of the First World War. A French program to create a high velocity selfloading rifle ended the same way, although their 7mm Meunier cartridge did see some service in that conflict with the A6 Meunier rifle that fired it. The Russians also sought a magnum-power infantry cartridge; Captain Vladimir Fedorov designed a semiautomatic rifle firing a high velocity 6.5mm caliber which never saw service; the rifle was eventually produced in limited numbers as a select-fire weapon in the weaker 6.5x50SR Japanese caliber.


.303 British Mk. VII, .280 Ross, .276 Enfield


The outbreak of World War I was the end of this line of development. New projectile technologies, and new infantry weapons undid the previous paradigm of long-range infantry rifle fire. The future would be dominated by the larger-caliber, more moderate velocity universal round…

Nathaniel F

Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. In addition to contributing to The Firearm Blog, he runs 196,800 Revolutions Per Minute, a blog devoted to modern small arms design and theory. He is also the author of the original web serial Heartblood, which is being updated and edited regularly. He can be reached via email at nathaniel.f@staff.thefirearmblog.com.


  • Edeco

    I have a thing for Ross rifles. They’re pretty, and the evil reputation sounds like opportunity to me. I mean, I wouldn’t use one without cleaning it and re-assembling it myself first, but then should be fine. Problem is caring for a vintage long gun.

    I read where Ross’ last words were something like “Get the hell out of here.”

    • 6.5x55Swedish

      Ross was a special kind of man. The rifle was a solid rifle but not very good as a military rifle (though it may have been good as a sniper rifle). Had they made sure that Ross best friend wasn’t the man in charge of overlooking the project it could have turned out to be a fantastic rifle. The bad reputation came from issues with production and the bad ammunition. The rifles worked well with the good Canadian ammo but the Brittish was just not good enough. Canada also had a hard time finding good steel. Education on the rifle was also bad.

  • 6.5x55Swedish

    It would be interesting to see what calibers we would have today if WW1 never came to be.