The development was primarily the work of Hall, who had been working on a design in the first two decades of the 19th century, receiving critical patents during the time. The work caught the interest of Army, which led to the contract at the end of the latter decade. The breech-loading design was made possible by his focus on using carefully machined components to form a seal, but still allowing enough tolerance for the breech to be opened easily. While precisely machined for the time, the technology of the day didn't allow for tolerances close enough to make a satisfactory seal, which was also one of the biggest hindrances to the creation of a successful revolver until some years later. The Hall rifle offered a significant increase in rate of fire over muzzleloading rifles and muskets (mostly due to the fact that one didn't have to manipulate the long, awkward ramming-rod every time one loaded). However, the design suffered from the gas leakage around the interface of the separate chamber and the bore (much as gases escape from the gap between cylinder and barrel of a revolver), resulting in the necessity of a heavier powder charge that still produced much less muzzle velocity than its muzzleloading competition. No serious efforts were made to develop a seal to reduce the loss of gas from the breech. The penetrating ability of its .52-caliber ball for the rifle was only one third of that of the muzzleloaders, and the muzzle velocity of the carbine was 25 percent lower than that of the Jenks "Mule Ear" carbine, despite having similar barrel lengths and identical 70-grain powder charges.