The Sharps Carbine
The seven patents described below in chronological order show the evolution of the Sharps Carbine.a The Sharps design favored simplicity for its users; however, that required a high level of technicality. The first two patents focused on the breech and the priming system. By just moving the guard lever down, putting in a cartridge, pulling the guard lever up and cocking the hammer, the gun was ready to fire (as long as the magazine did not run out of primer). The third patent simplified the firing process even more, because the marksman did not even need to cock the hammer. Later, in the carbine’s sixth patent, the gun was able to use a percussion cap, which diversified the gun’s design to enable it to use two priming systems. The marksman switched between priming system by using a pin on the lockplate. Once again, the design offered the user little difficulty in activating a mechanism. The fourth and the seventh patent worked to perfect the explosion chamber-breech block seal. A good seal promoted user comfort as well as increased firepower. Finally, the fifth patent improved the Sharps sight. All of these patents’ innovation created a simple and reliably useful gun.
Because all of the patented improvements were done before the war and the gun was already seen in a positive light due to its success on the battlefield, the Sharps was able to build on their good reputation, rather than trying to build upon an idea that the gun was still a work in progress that needed improvement. The gun’s continued success and reliability as well as its pre-established design promoted the carbine to be one of the most popular during the Civil War.
1. September 12, 1848, Number 5,763
In this patent Christian Sharps claimed his invention to be the vertically sliding breech. The guard lever attached to the breech slide by a “stirrup,” what appears to be a rectangular metal piece. When the lever moved forward, the stirrup pulled the breech slide down, which then exposed the top of the barrel through the breech support. (The breech support is on both the front and back of the breech slide.) In that position, the cartridge was inserted into the barrel to be held by the counterboring at the top of the barrel. The counterboring positioned the cartridge so that with the back end of the cartridge hung slightly out of the barrel. Returning the guard lever to its original place pushed the breech slide back up, and the knife-edge on the slide’s side sliced the end of the cartridge, exposing the powder for the explosion. The breech slide contained the “cap-nipple,” where the hammer would strike the primer to create a spark. That spark went into the “fire communication,” a tube that led to the chamber, to ignite the powder, making the explosion. The primer was held in a tube attached to the side of the barrel that ran through part of the breech. The primer “caps” were pushed through the tube by a “follower” attached to a cord that winds around a cylinder. When the breech was returned to its closed position, a primed cap-nipple was in place as well as the cartridge. The carbine was then ready to fire.
2. October 5, 1852, Number 9,308
In this patent, Christian Sharps perfected his system of priming a carbine. A vertical tube that held the priming pellets was built into the lockplate. The tube had a piston attached to a helical spring that rested on the screw that closed the bottom of the tube. As less and less pellets occupied the tube, the spring pushed the piston up, so that the pellets always remained at the top of the tube. There was an arm attached to the “driver” that pushed or threw the pellets. Part of the arm fit into the right-angle groove in the side of the hammer. When the hammer was fully raised, the driver was in its farthest back position, and one pellet is raised by the spring and piston. Pulling the trigger moved a small sliding piece up to release the hammer. When the hammer fell, it pushed the driver forward. Then, the driver struck the pellet and threw it between the closing hammer and the nipple right as the hammer came down to hit the nipple, and the gun fired.
2. US Patent No. 9,308
This patent drawing describes the Sharps carbine's pellet priming system.
These drawings are from Christian Sharps' 1852 patent accessed through Google Patent Search. The drawings were labeled by Brittany Venturella and correspond with the patent's description.
This patent drawing displays an improvement to the sealing ring of US Patent 14,554 (listed as number 4 on here).
These drawings are from Richard Lawrence's 1859 patent accessed through Google Patent Search. The drawings were labeled by Brittany Venturella and correspond with the patent's description.
3. March 13, 1855, Number 12,529
Inventor Rollin White patented a self-cocking hammer that connected itself to the carbine breech. By moving the guard lever back into the breech-closed position, the breech chamber that just moved vertically into place caused a “tooth” attached to the sliding breech to pull back the tumbler, cocking the hammer.
4. April 1, 1856, Number 14,554
In this patent, Hezekiah Conent claimed the right to what became the first successful check to block gas from leaking from the explosion chamber. Because the gas stayed inside the chamber at the top of the barrel, his invention allowed the gun to be safer and to have more power. He placed a metal ring, which had straight or slanted edges in order to fit properly into the breech-slide, into a slightly dug out circle, whose depth corresponded with the ring’s thickness. The dugout circle, or “orifice,” was either “concaved out” (had slanted edges) or “chambered” (had straight edges). The inner diameter of the ring was the same size as the bore. The powder’s force during the explosion caused the ring to expand, sealing the breech and not allowing any gas to leak through the joint of the barrel and the sliding breech.
5. February 15, 1859, Number 22,958
In this patent, Richard Lawrence’s invention was the improvement of the rear sight, which would have been used in the 1859 model and subsequent models. The sight had a spring base attached to the barrel by a screw or stud. According to the patent, Lawrence claimed the right to the sight having a “hinge-joint in connection with an elevator” (but not the elevator itself). The hinge-joint allowed the sight to fold down or up and was made out of a metal tube, which connected to the rest of the sight with “ears” or holes in the bottom of each side of the sight.
6. April 12, 1859, Number 23,590
Inventor Richard Lawrence patented a way to stop or lock the pellet primer when the marksman wanted to use the hammer without the primer and use percussion caps instead. He made the back of the driver almost double the thickness of the pellets, while keeping the front thickness just more than that of the pellet. When the driver was thrown forward, the thickness of the driver landed over the primer magazine’s hole where the pellets would have came out. The tip of the driver was shaped like a wedge. When the driver slid forward, trying to get a pellet out of the magazine, the wedge actually forced down all the pellets in the magazine. The “shut off,” or “cut-off” mechanism was placed under the driver and had a lip on it that also helped to stopped the pellets from coming out. When the shut off was over the magazine hole, it detached itself from the driver by slightly moving down and stopped any more pellets from going out of the magazine. A pin on the top edge of the lockplate allowed the marksmen to control the “shut off,” turning it on and off. When a cover was over the driver and the pin, the shut off could be stopped and started by a metal tooth and two notches. When the tooth was in one notch, the shut-off was on, and when the tooth was in the other notch, the shut-off was off.
7. December 20, 1859, Number 26,504
In this patent, Richard Lawrence improved upon Hezekiah Conent’s patent for the expanding ring to seal the breech. His invention attached Conent’s ring to a metal plate with a circular opening that lined up with the barrel’s opening. The ring was on the opposite side of the plate than the barrel. The ring had concave edges on its inside. Lawrence placed a cone in the center of those concave edges so that the cone’s and ring’s edges were parallel. When gas filled the chamber, the plate pushed against the barrel’s edge, and the thin edge of the ring expanded, filling the space between the cone and the ring. The cone and ring sealed the breech. The plate solidified Conent’s loose ring so the ring did not damage the barrel or make the sliding breech difficult to operate.
a According to Winston O. Smith in The Sharps Rifle, there were nine patents that played a part in the advancing technology for the Sharps, and four of them belonged to Richard Lawrence.1 The other possible Lawrence patent is number 8367 that Lawrence patented in Windsor, Vermont on January 6, 1852. However, that patent was for a different type of breech than that used in the Sharps. The breech rolled to the side to insert the cartridge and is not powered by a guard lever. The other patent, number 6960 dated December 18, 1849, is from Christian Sharps. That patent was from right before he helped establish the Sharps Rifle Manufacturing Company. That patent description pertained to a revolving pistol, and not a carbine or rifle. Christian Sharps’ later patents, starting in 1856, would have been written after his break with the company. The author has not found another patent that can be contributed to the Sharps.
1 Winston O. Smith, The Sharps Rifle: Its History, Development and Operation (New York: William Morrow & Company, 1943), 47.