a tight-fitting projectile can be used, as it doesn't have to be forced down the barrel, which allows the use of rifling as well as a fast rate of fire. This fact means that even a breechloader that only achieved the same rate of fire as a muzzle-loading musket would still be superior to the musket, as the breechloader could be rifled and the musket couldn't, although in fact, breechloaders generally also had a greater rate of fire. 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. Thousands of rifles were made, though the troops and many leaders preferred the simplicity and lower costs of muzzle-loaded weapons. However, the advantages were clear, and breech-loading designs would grow to dominate rifle procurement after the Civil War. Many of the lessons learned by Hall would benefit designers of