The Post-Civil War Springfield in .50-70: Behind the Trapdoor

The post-Civil War Trapdoor Springfield is now 159 years old. A stopgap arm meant to help the United States husband money after the war, it served for more than 30 years and even aided training in World War I. The Army was certain its next rifle was to be a breechloader utilizing the vastly superior metallic cartridge. This priority had to mesh with a civilian leadership that insisted the 1 million muzzleloaders in inventory be utilized—somehow.

The first effort led to the manufacture of the .58 Rimfire Model of 1865 Breech Loading Rifled Musket designed by Springfield Armory’s master armorer Erskine S. Allin. Manufacturing of rimfire ammunition was fairly well understood, and the .58 Rimfire duplicated the paper cartridge used in the muzzleloading Springfield musket. The Model 1865 and its cartridge weren’t very successful, though, and only 5,005 were produced between 1866 and 1867.

The rimfire was a dead end. The creation of the new centerfire priming technology culminated in the Army adopting a cartridge with a copper case using an inside primer crimped into the base. Copper was necessary because it was soft enough that the firing pin could ignite the primer inside, but copper doesn’t have the expansion/contraction properties of brass, and spent cases often stuck in the chamber. Copper was another dead end in cartridge development, but it took the U.S. more than another decade to change.

The final recommendation for a new cartridge came from the Hancock Board of 1866. It chose a smallbore (any bullet under half-inch was considered a “smallbore”) .45-inch bullet over 70 grains of powder in a straight case with a bullet weighing 480 or 500 grains. Chief of Ordnance Gen. A.B. Dyer nixed that, saying the cartridge was too long for easy use and too small in caliber.

The board highly recommended Gen. Hiram Berdan’s bolt-action rifle submitted with his very modern .42-inch paper-patched bullet atop a drawn brass bottleneck case ignited by his patented Berdan primer. Second was a forgotten rifle submitted by a Maj. Yates. The third was the Remington rolling block—which was soon to arm many of the world’s armies—and the fourth was the equally long-forgotten Roberts.

Conversion?

The fifth choice was Springfield Armory’s Allin conversion. Of consideration in selecting Allin’s “Trapdoor” was the government wouldn’t have to pay royalties to Berdan. Allin sold his patents to the U.S. for $1. Meanwhile, a frustrated Berdan barnstormed Europe, and soon almost every country on Earth adopted a variation of his bottleneck cartridge.

When the choice was made to downsize the .58 rimfire to a .50, there were so many .58 musket barrels in inventory that Springfield chose to reline them to .50 inch. Allin simplified and improved the breechblock system for the new Model of 1866 chambering the new centerfire .50-70 cartridge. A total of 52,300 Model 1866s were made between 1867 and 1869.

All this lining jazz soon proved costly. Reaming a liner smooth, reaming a musket barrel smooth, inserting then brazing them at both ends, rifling the newly joined parts, then machining the breech area to accept the trapdoor with its associated extractor parts and springs proved not only expensive but time-consuming. And after all that, occasionally a liner would walk out under recoil anyway.

Creating a separate receiver for the action parts, then screwing in a newly made barrel, proved simpler, cheaper and sturdier. The Model of 1868 was born.

Not Quite a Frankenstein

The squat .50-70 Gov’t centerfire cartridge firing a 450-grain bullet at around 1,250 fps in an inside-primed copper case would be short-lived, but we finally had a breechloader. Springfield Armory made 52,145 Model 1868 rifles between 1869 and 1871. Sadly, the copper-cased ammunition would plague the Army for many years—first in the .50-70, then in the .45-70.

The Model 1868 infantry rifle was finished “in the white.” The finish on my rifle has tarnished over the last 150-plus years to a mottled gray with light pitting from years of neglect. Springfield Armory experimented with nickel plating and painting with lacquer to inhibit rust, but none proved durable, while the slow rust brown/blue finishes were judged too time-consuming.

The new .50-70 barrel was shortened from the 40 inches of the Model 1863 musket to a handier 329/16 inches with three-groove rifling having a twist of 1:42. Stocks were shortened to 48.75 inches using two bands instead of three, with the sling swivel band moved to the muzzle.

The shorter stock reduced the overall length to 5113/16 inches, and the rifle weighed nine pounds, two ounces with the sling. In another cost saver, the one-piece Civil War musket slings were cut in the middle and sewed together to fit the new swivel distance.

Relic Stamps

The Civil War musket locks retain their original date of manufacture, and mine is dated 1863 behind the hammer. Ahead is an eagle and “U.S. Springfield.”

These locks have a two-notch tumbler. The first notch doesn’t raise the hammer high enough to open the breech, so the rifle must be fully cocked to load. The trigger pull is a whopping 11.5 pounds, although it breaks cleanly. As an aside, these early two-notch locks can have a fly added for the use of set triggers. Gen. George A. Custer had an 1866 altered into a sporting rifle with set triggers, half stock and pewter fore-end cap.

Atop the breechblock is the date of manufacture—1870 in this case—an eagle and “U.S.” The serial number on the left side of the receiver matches the one on the barrel. The stock should have “ESA” in an oval on the left side, but such markings were faint and easily worn away.

The three-leaf Civil War musket rear sights were finally retired. A new single-staff folding sight with a sliding leaf graduated from 200 to 900 yards was mated with an inverted “V” front soldered to the barrel. No windage correction was provided.

Dust on the Design?

Many deride the trapdoor design as weak and tout the considerable breeching strengths of its contemporaries—but these rifles were thoroughly strong enough for the day’s ammunition.

The trapdoor system offered simplicity and a high rate of fire. Cock the hammer, flip open the breech and insert a cartridge. Importantly, you don’t have to push the round in completely to close the trap, unlike almost all other single-shot systems. After firing, cocking the hammer and lifting the trap ejects the spent shell clear of the gun for quick reloading.

The .50-70 Trapdoor underwent a final modification, becoming the Model of 1870. Between 1870 and 1873, 11,531 of this model were made. These .50s offer much for the collector to pursue. Four distinct infantry models and several Cadet models make for an interesting collection. The more common ones like mine 1868 sell for around $1,000. That so many went from the Army to become buffalo hunters just adds to their glory.

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