The MkIV Martini-Henry Enfield rifle. “A” is ready to load & “B” is ready to fire. It was a breech-loading lever actuated rifle – used from 1871 by the British Army, throughout the British Empire, for more than 30 years – remaining in service until the end of WW1. “Enfield” refers to the Government’s Royal Small Arms Factory in London where the rifle was mannufactured. Length 49″, could fire 12 rounds per minute, effective range 400 yds, max range 1,900 yds
Picture and details from the internet