Carabine à tige
The carabine à tige, sometimes called a stem rifle or pillar breech rifle, was a type of black-powder, muzzle-loading rifle invented by Louis-Etienne de Thouvenin. The method was an improvement of the invention of another Frenchman, Henri-Gustave Delvigne.
Delvigne had developed chambered carbines and rampart rifle-muskets so that when forced against the chamber rim by ramming, the bullet would become deformed and flatten, so as to expand in diameter against the inside of the bore, allowing the bullet to press against the rifling grooves. When fired, the bullet accompanied the rifling and spun. This was an early attempt to work around one of the greatest hindrances to the use of military rifles; in order for a rifle to impart the proper spin to a projectile, the projectile must fit snugly inside the barrel to engage the rifling grooves.
The problem, however, was that the black powder used at that time would quickly produce a thick layer residue of fouling. After only three or four shots, a typical rifle would be impossible to reload without using a mallet to force the bullet down the fouled barrel.
Delvigne's design addressed this problem by introducing a projectile that was smaller than the bore of the barrel which after loading could then be struck with a ramrod. With three strokes of the ramrod, the bullet would become deformed and flatten, so as to expand in diameter against the inside of the bore, allowing the bullet to press against the rifling grooves. When fired, the bullet would accompany the rifling and spin. This improvement preserved accuracy while reducing the time required for reloading which would otherwise have been necessitated by the heavy fouling.
Carabine à tige
Thouvenin's improvement involved a steel stem inside and at the center of the powder chamber, around which powder was inserted, and on top of which the bullet was dropped. When hit by the ram, the bullet expanded radially against the rifling grooves and at the same time wrapped around the stem, giving it a more efficient and aerodynamic shape. Thouvenin published his invention in 1844.This system, although an improvement over Delvigne's method, still did not allow for a perfect engagement in the rifle, rendering the ball's trajectory rather erratic. The French Army, however, adopted the improvement in 1846. The Chasseurs adopted the system in 1853, as did the Prussian Jägers corps, where marksmen skills were essential.
The rifles were known as Thouvenin tige rifles. The weapons used a 600 yards sight and a hair trigger. The barrels were rifled with eight grooves, making a turn every 36 inches.
The Thouvenin rifles had the inconvenience of being very difficult to clean, especially the area around the stem.