The safety tab combined with the notch in the striker appears that it might prevent the striker from moving forward more than about 0.1". However I'm not sure the geometries of the parts are actually suitably designed to overcome the very strong striker spring used, especially given a small running start of the striker. It's not easy to test the reliability of the striker notch/safety tab without permanently altering the safety, so I haven't tested it myself. Don't get me wrong, I like and use a Hawkeye myself. I'm just attempting to accurately represent the design.I think the Ruger locks the striker in position 3...
Winchester's bolt shroud mounted safety is considerably different in the details, but the Ruger design does offer functionality that is somewhat similar, if not completely suitable. Though I greatly prefer the Winchester M70 safety and trigger design over the Ruger, I always seem to find Rugers instead of Winchesters when I'm looking for a hunting rifle. So I've hunted mostly with the Rugers; with success, and without incident.