Mark II M-H Artillery Carbine Mark III Receiver body has rounded lower front corners to make sliding the rifle into a saddle bucket easier. Small cocking indicator to reduce snagging when used in saddlebuckets. Forearm secured by the hook arrangement found in the MkIII and MkIV Martinis. Barrel 21.375 Inches in length with a new, reshaped knoxform at the rear of the barrel.
Front sight has a thinner barleycorn with wings to protect the sight from saddle-wear.
Two bands secure the barrel to the forearm. In 1879, a leather sight cover was devised. This required a wood screw be installed on each side of the forearm just below the rear sight. The leather cover has ears that hook over the screws to protect the sight from snagging and accidentally changing the range setting, and saddle-wear. Lower sling swivel was removed, but some models were later modified with lower sling swivels.