. 30 - 03 The . 30 - 03 was a short - lived cartridge developed by the United States in 1903 , to replace the . 30 - 40 Krag in the new Springfield 1903 rifle . The . 30 - 03 was also called the . 30 - 45 , since it used a 45 grain ( ) powder charge ; the name was changed to . 30 - 03 to indicate the year of adoption . It used a 220 grain ( ) roundnose bullet . It was replaced after only three years of service by the . 30 - 06 , firing a " Spitzer " bullet giving better ballistic performance . Initial development . The . 30 - 03 was developed to replace the . 30 - 40 Krag cartridge used in the Krag - Jørgensen rifle , which was the first bolt action rifle adopted by the US military , and the first that used smokeless powder . The Krag - Jørgensen rifle had some serious limitations compared to the new Mauser rifles being used by European armies ; it was loaded one round at a time , rather than using a stripper clip , and the Krag - Jorgensen ' s single locking lug on the bolt made the action much weaker than the strong , two lug Mauser bolt , limiting the power of the round . A new rifle was designed , using the Mauser as a guide , and a new cartridge was designed for it . The new cartridge was more powerful , using a 45 grain ( 2 . 9 g ) charge of smokeless powder , 5 grains ( 0 . 3 g ) more than the . 30 - 40 . The bullet was the same , a . 30 caliber , 220 grain ( 14 g ) round nosed jacketed bullet , at a higher velocity of 2300 feet per second ( 700 m / s ) , compared to the 2000 feet per second ( 610 m / s ) of the . 30 - 40 Krag . The new rifle was also the first in a trend of shorter infantry rifles ; the 24 in ( 610 mm ) barrel was halfway between the standard rifle and the carbine used by the cavalry , and thus there was no carbine variant of the 1903 rifle . The . 30 - 03 cartridge was also a rimless design , which allowed better feeding through the box magazine than the old . 30 - 40 Krag case . The Model 1895 Winchester lever action rifle was offered in 30 - 03 from 1905 , but sold poorly in comparison to the . 30 - 06 chambering offered in 1908 . Problems . The . 30 - 03 cartridge suffered from the start . It caused severe erosion of the bore of the rifle , due to the high pressures and temperatures needed to push the heavy bullet to the desired velocity . The heavy bullet was also an issue ; the 220 grain ( 14 g ) bullet was aerodynamically inefficient and had a very curved trajectory ( see external ballistics ) so it was not well suited for long range shots . It was also unfashionable , since most countries were switching to a 7 or 8 mm cartridge firing a lighter , around 150 grains ( 9 . 7 g ) , spitzer pointed bullet at a higher velocity . This gave better energy retention and a flatter trajectory . The . 30 - 03 was shortened slightly by in the neck , the powder was reformulated to burn cooler , and the bullet was changed to a 150 grain ( 9 . 7 g ) spitzer bullet , creating the . 30 - 06 cartridge . Since the new . 30 - 06 was shorter than the . 30 - 03 , it could fire in 1903 rifle , but with poor accuracy . The 1903 rifles were all recalled , fitted with the Model of 1905 sights and bayonet , and rechambered for the new . 30 - 06 cartridge . This last procedure was done by unscrewing the barrels , milling off the end of each chamber , re - threading the barrels , rechambering them and screwing them back on the same actions . This ended the short life of the . 30 - 03 ; out of nearly 75 , 000 made , no more than a handful of original 1903 rifles escaped the conversion to . 30 - 06 ( estimates range from 50 to 100 rifles ) , becoming rare collectors items . Even the . 30 - 03 cartridge is a rarity , found only in collections of rare cartridges . The . 270 Winchester cartridge was based on reducing the neck diameter of a . 30 - 03 cartridge case to retain a similar bullet - holding length with the same shoulder .