The Ruger M77 Mark II, a bolt action rifle designed by Sturm, Ruger & Co. in 1991, is the sucessor to the Ruger M77. The M77 Mark II is a refined version of the M77, having been almost completely redesigned and re-tooled.
The major changes to the M77 that were made to produce the M77 Mark II were to the safety, trigger and bolt. The original two tang safety has been replaced by a three position mechanism which allows the chamber to be loaded and unloaded while the bolt can move (as well as locking it in position to prevent it moving all together). The original trigger has also been replaced, with a two-stage trigger designed to remove large amounts of movement and weight in the trigger to make firing easier.
However a significant number of elements from the original design have remained. The Mauser style extractor system (which had originated on the Mauser 98) was slightly modified for a better ejection performance but remains virtually identical to the original. Likewise the integral scope mounts, cut into the rear of the receiver, remain as does the one piece, stainless steel, bolt handle.
The M77 Mark II fires a range of smaller calibre cartridges, from Ruger's own .204 Ruger cartridge to the .308 Winchester (used by most of the M77 Hawkeye and Gunsite Scout lines). Other cartridges include to .223 Remington, .22-250 Remington and the 6.5mm Creedmoor. Magazine capacities vary depending on the cartridge used, with the .204 Ruger and .223 Remington shot from five round box magazines while the others shot from four round capacity magazines.
The M77 Mark II is currently marketed as the M77 Mark II Target Rifle, with one possibility as to why being that Ruger would prefer the user to use the M77 Mark II as a competition rifle, while the M77 Hawkeye (effectively the M77's current guise) would be used by small game hunters and "varmiters" (hunting small rodents). The M77 Mark II formed the basis of another of Ruger's firearms, the Ruger Gunsite Scout, a project that was developed with the Gunsite Training Centre to construct a scout rifle, unveiled in 2011.