With the hammer down and a round in the chamber,and the hammer recieves a blow the round will fire. The newer models have a crossbolt safety. I find the 1/2 cock fine. I have a .444 Marlin which is the same as the 336 just a different caliber . I have a scope mounted onmine and I removed the entire front site( removed the screws from the ramp). The scope fits over the rear site with no modification.