I am hoping there is a Ruger expert here who can advise me on the twist rate of my rifle. I want to try some bullets heavier than the 55's it shoots fine. I am reluctant to purchase a 100 bullets and then find they are too heavy for my gun. The rifle is an early model 77 Mark 2 (so called transitional model- it has a blued receiver and a heavy stainless factory barrel) in 223. The serial # is 781-44xx. Thanks for any help.


















































