I've shot probably 250 170 gr. Remingtons through my Marlin 336, two of them at deer, the rest through paper. They kill paper beautifully, but failed miserably on the deer, both shot through the boiler room. The first went almost a quarter mile and was killed, stumbling, by another hunter. The second was shot as a blizzard was moving in and I couldn't wait for it to lay up because of snow cover. The storm got so bad so quickly the blood and tracks were covered. I did a couple of large figure eights looking for it before I had to give up, afraid of being disorientated. The next morning, I followed the crows and ravens and found the deer more than 300 yards from where it was shot, half eaten by coyotes.
I've used 170 gr. Winchester silvertips in that same rifle for all of 50 years. I never lost one out of at least 35 deer, and I don't ever remember having to use a second shot. The first deer I killed with that rifle and the Silvertips was an open sight head shot at 168 paces at age 17. The second, the same day, was 225 yards known distance between fence lines. Hit in the heart lungs, it went 50 yards pumping blood out both sides, jumped a stone fence and was dead on the other side. The snow looked as if you had taken a 5 gallon bucket and poured blood across the field. The Remington shot deer, shot through, left a fine spray of blood you might find here and there. It has been my opinion, possibly incorect, that the Cor-Lokts don't open fast enough in the slow .30-30. Friends of mine use them successfully in their '06s.