Springfield Model 1870 Trapdoor Carbine

Springfield Armory (US Government) · Carbine · Discontinued · 1871

Also known as: Model 1870 Carbine, Springfield Trapdoor Carbine (1870), Allin Conversion Model 1870 Carbine

Overview

The Springfield Model 1870 Trapdoor Carbine is a single-shot, .50-70 Government breech-loading carbine built at the U.S. Springfield Armory using Erskine S. Allin's hinged trapdoor breechblock. A shortened cavalry version of the Model 1870 rifle, it fitted a 22-inch barrel, a saddle ring and bar, and a rear sight graduated for mounted use. Only a few hundred were produced in 1871, making it one of the rarest of the martial trapdoor carbines and a transitional design between the .50-70 conversions and the later .45-70 Model 1873.

Specifications

Weight (empty)3200 g (112.9 oz)
Overall Length1048 mm (41.26")
Barrel Length559 mm (22.01")
Action TypeTrapdoor
Firing MechanismHammer Fired
Trigger TypeSingle Action
Magazine Capacity1 rounds
Muzzle Velocity366 m/s (1201 fps)
Muzzle Energy1953 J (1440 ft·lbf)
Effective Range275 m (301 yd)
Maximum Range640 m (700 yd)
Barrel RiflingRight Hand
Rifling Twist1067 mm (42.01")
Number of Grooves3
Frame MaterialSteel
Barrel MaterialSteel
Stock MaterialWalnut
FinishBlued

Calibers

Features

Production

Estimated total produced: 361 · Production years: 1871

About 341 carbines made April-June 1871 with possibly around 20 more October-December 1871; far scarcer than the roughly 11,000 Model 1870 rifles.

Origin

Country of origin: United States

Designer: Erskine S. Allin

Discontinued: 1872

Notes

Produced in extremely limited numbers (roughly 341 to 361 carbines) between April and December 1871; stocks bear the single ESA cartouche and the carbines were not serial numbered.

Background

The Model 1870 carbine occupies an unusual footnote in U.S. martial arms: chambered in the aging .50-70 just as the Army was moving to standardize the .45-70, only a few hundred were ever built. Its rarity and the single ESA cartouche make surviving examples among the most sought-after trapdoors by collectors.