Rifle barrel chamber mechanism. This drawing show a cup mechanism (top) and a needlepoint which were designed to expand the base of the bullet into the barrel rifling. Year: 1850. Image Credit: Smithsonian Neg. No. 91-10730; Harpers Ferry NHP Cat. No. 13646.

Harpers Ferry NHP Catalog No. burt-15. You may purchase duplicate copies of this image from the Harpers Ferry Historical Association. Please call 304-535-6881 for more information, or email the Harpers Ferry Historical Association.