In 1836, Samuel Colt invented the revolver design which continues to be used to this day. Colt's Manufacturing Company hired Elisha K. Root to modernize production, making Colt weapons the first in the world with truly interchangeable parts. Horace Smith and Daniel B. Wesson designed the first repeating rifle in Norwich in the early 1850s, which went into production by the New Haven Arms Company (which later became the Winchester Repeating Arms Company), and, just across the border in Massachusetts, the Springfield Armory. Smith also patented a metallic rifle cartridge in 1854. Christian Sharps designed the Sharps breech-loading rifle which in 1854 began to be manufactured in Hartford by the Sharps Rifle Manufacturing Company. Christopher Spencer designed the Spencer repeating rifle which played an important role for Union troops at the Battle of Gettysburg.