.45-70

.45-70 Government
45-70 Sample.jpg
From left, .30-06, .45-70, and .50-90 Sharps
TypeRifle
Place of originUnited States
Service history
Used byUnited States
WarsIndian Wars, Spanish–American War, Philippine–American War
Production history
DesignerUS government
Designed1873
Specifications
Case typeRimmed, straight[1]
Bullet diameter.458 in (11.6 mm)
Neck diameter.480 in (12.2 mm)
Base diameter.505 in (12.8 mm)
Rim diameter.608 in (15.4 mm)
Rim thickness.070 in (1.8 mm)
Case length2.105 in (53.5 mm)
Overall length2.550 in (64.8 mm)
Rifling twist1-20"
Primer typeLarge rifle
Maximum pressure (SAAMI)28,000 psi (190 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
300 gr (Trapdoor) lead PB 1,597 ft/s (487 m/s) 1,699 ft⋅lbf (2,304 J)
405 gr (Trapdoor) lead FN 1,394 ft/s (425 m/s) 1,748 ft⋅lbf (2,370 J)
300 gr (standard) JHP 2,069 ft/s (631 m/s) 2,852 ft⋅lbf (3,867 J)
300 gr (strong) JHP 2,275 ft/s (693 m/s) 3,449 ft⋅lbf (4,676 J)
Test barrel length: 24"
Source(s): Accurate Powder[2][3][4]

The .45-70 rifle cartridge, also known as .45-70 Government, was developed at the U.S. Army's Springfield Armory for use in the Springfield Model 1873, which is known to collectors as the "Trapdoor Springfield." The new cartridge was a replacement for the stop-gap .50-70 Government cartridge, which had been adopted in 1866, one year after the end of the American Civil War.