I have an three older 77 Mk IIs and am pretty sure the triggers are the same as the Hawkeye. I use mine single shot, have a single shot sled sitting above the mag spring on all of mine - 223, 25-06, 6.5 Creedmoor. No issue with the extractor sticking over the rim when I do single shot "push feed" on any of them.
The Ruger trigger is a "sort of 2 stage" in that there is significant take up followed by resistance and then "click" - the trigger pull. The 1st stage is very soft, sort of like an Enfield with resistance instead of hanging free (hopefully that helps). It's not so soft that you'd pull through the 1st and accidentally trip the trigger. It is readily adjustable, but I don't know if you could safely get under 1lb. I'm about 24 oz, but to test I slam the heck out of the action and if the sear slipped increased engagement. If one clipped the 1st stage trigger return spring, lightened the trigger spring, got sear engagement just right and was committed to slowly working the action .... I think you could.
In addition to the nice stock, I think the Ruger Varmint trigger is also very good and really under appreciated. I do wish the barrel was just a touch heavier at the muzzle though.
