From the beginning, the Ruger M77 was intended as a modernized Mauser 98, though numerous changes were made. Bill Ruger wanted to use investment casting in place of a forged receiver. The Sullivan-designed bolt dispensed with the Mauser blade-type ejector and instead used the simpler plunger style of the ejector. A two-position tang safety and redesigned trigger system were also designed from scratch
6.5 Creedmoor Laminated Stock Rifle M77
Perhaps the most novel feature of the M77 is the only one that has not been redesigned, the angled action screw. The front action screw of traditional bolt-action rifles draws the receiver directly down against the stock. The M77 uses an angled screw that draws the action down and to the rear, tightly bedding it against the stock.