Model 1866 U.S. Breech-Loading Rifle with an Allin Conversion – 2nd Model Allin Trapdoor Springfield


Model 1866 U.S. Breech-Loading Rifle with an Allin Conversion – 2nd Model Allin Trapdoor Springfield – This breech-loading rifle was the second iteration of Allin conversion rifles. Approximately, 25,000 Civil War era, Springfield Model 1863, rifled muskets were converted from muzzle-loading, percussion muskets, to breech-loading, metallic cartridge rifles. These rifles’ barrels were bored and a liner tube of .50 caliber inserted; the rifle fired a centerfire cartridge. The M1863 Springfield’s three-barrel bands with band springs were retained. The lock plate retains its Civil War period stampings – “Springfield”, Eagle and the date “1864”; the breech block’s loading door is marked “1866” over an eagle’s head. Mountings and finishes remained the same as the Civil War period, M1863, with metallic elements finished bright. The breechblock has a somewhat blackened finish, while the lock and hammer have a brighter, casehardening finish. The rifle remains in overall good condition – clean bore with rifling remaining; bright finish has turned to a light brown; firing action good; original dark walnut stock finish with some use dings; original sling; regimental or rack number stamped on the butt stock.

These M1863 Springfield muzzle loading, Civil War issue rifles were converted shortly after the war, starting in 1866. The U.S. Army was somewhat slow to adopt new technological advances in firearms and initially opted to retrofit the sizable surplus inventory of muzzle loading muskets to enable them to fire metallic cartridges. Several varieties of conversion modes were implemented; this rifle is an example of the one named for its inventor, Erskine S. Allin, Master Armorer for Springfield Armory.

This Springfield Model 1866 was the second iteration of the Allin designed trapdoor breech-loading mechanism. Originally developed as a means of converting rifle muskets to breechloaders, the Allin modification ultimately became the basis for the definitive Springfield Model 1873 Trapdoor, the first breech-loading rifle adopted by the United States War Department for manufacture and widespread issue to U.S. troops.

These conversions were the essential infantry weapon on the U.S. frontier and played a large role in the Indian Wars of the late 19th century. Approximately 25,000 .58 caliber Springfield Model 1863 rifled muskets were converted by the Springfield Armory for use by U.S. troops, the barrels being relined and rifled to .50 caliber and the trapdoor breech system affixed. The rifle was chambered for the powerful centerfire .50-70 Government cartridge.
Caliber: 50-70 cartridge

Overall Length: 56″

Barrel Length: 39.5” (from breech plug and including trapdoor)