January 04, 2019
By Dick Metcalf
The traditional .45-70 load put a 405-grain, .458-caliber lead bullet over 70 grains of blackpowder, hence the .45-70 designation, sometimes rendered .45-70/405.
Subsequent standard-power smokeless-propellant .45-70 405-grain ammunition paralleled that performance, providing a muzzle velocity of about 1,330 fps and 1,590 ft-lbs of muzzle energy at a Maximum Average Pressure (MAP) of 28,000 CUP, which will down any North American game at less than 100 yards.
.45-70 Government Case: FederalCase Capacity: 81.1 grains of waterPrimer: Federal 210Case Length: 2.105 inches OAL: 2.550 inches
More recently, several ammomakers have added higher-velocity 300-plus-grain JHP loadings at 1,800-plus fps catalog velocities to improve the .45-70's performance range out to as far as 200 yards, and some specialty-load manufacturers have even pumped up a variety of "+P" (35,000 CUP) .45-70 loadings with hardcast bullets as heavy as 540 grains at 2,500 ft-lbs that can be used with confidence in the face of any dangerous game on the planet, including Alaskan brown bear, Cape buffalo, or elephant. The modern Marlin Model 1895 can handle them all.
The .45-70's straight-wall configuration and large caliber make it extremely easy to handload. But buy a lot of powder; it's a big case. Handloading guides for the .45-70 commonly provide at least two different categories of loadings, one for 19th-century-design firearms and replicas, the other for stronger, modern arms like the post-1973 Marlin Model 1895 or Browning and Ruger falling-block-type single-shots.
My favorite loadings for modern .45-70s are shown in the chart. As their velocities indicate, you should not use these loads in an antique or replica gun unless you're looking to turn it into a metallic jigsaw puzzle.
Metcalfs's Favorite .45-70 Handloads Bullet Powder (type) Powder (grs.) Velocity (fps) Comments Hornady 300-gr HP H4198 52.0 2073 Expanding load; deer/elk to 200 yds. Hornady 300-gr HP Reloader 7 50.0 2011 Expanding load; deer/elk to 200 yds. Sierra 300-gr FNHP IMR-3031 55.0 1932 Expanding load; deer/elk to 200 yds. Sierra 300-gr. FNHP IMR-4895 60.4 2004 Expanding load; deer/elk to 200 yds. Hornady 350-gr. RN H322 52.0 1825 Good load for black bear/moose Hornady 350-gr. RN H4895 60.4 2004 Good load for black bear/moose Speer 400-gr. FNSP IMR-4198 43.0 1730 Effective bison load Speer 400-gr. FNSP IMR-3031 58.0 2918 Effective BIG bison load NOTES: Instrumental velocity is the average of five rounds measured 10 feet from the muzzle of a 22-inch-barreled Marlin 1895. Use these loads only in modern .45-70 firearms rated for high-pressure ammunition.
