Notice that adjustment technique eliminates the need for  a palm rest 

If a .264 Win failed to kill that stick, how'd they manage to kill all those antelope and deer, etc.?

My guess: you hit that rock that was sitting there a foot in front of him.

I used to shoot a lot of "rockchucks" Yellow Bellied Marmots at an elevation of less than 3000 ft. just north of Mt. Shasta California, near Weed. My grandparents lived in Mt. Shasta where my grandfather was the only plumber for miles. Thus he knew a lot of the locals, and sent me to a rancher who was more than glad to have me thin his herd. At that time, used a 222 Rem.mag. that was more than adequate, as the chucks holed up in and beneath fence rows made up of volcanic rock from fields cleared for growing hay, and most of the shots were 100 to 300 yards. The only rule was head shots only, as a way to assure future opportunities. The largest chuck I ever shot weighed a verified 16 lbs, at the local pharmacy (owned by my grandmother) it was called Windsor's. A good friend Lee Six used a 22 Harvey Rockchuck, Named after Stu Harvey. It was a shortened 284 winchester necked to 22 caliber. It was a lot of cartridge for the ranges I would shoot, but not for the 4 to 5 hundred yard shots Lee Would take. Like Westerner, I can no longer shoot anything unless of coarse I felt threatened by those long front teeth! Then all bets are off. I look back favorably on those days spent in the shadow of beautiful Mount Shasta. These were single shot rifles, but not in the traditional sense. I did shoot quite a few with trditional single shots, Stevens in 25-20ss and 25-21 at much shorter ranges as they are fairly tough animals even when attempting head shots. My favorite rifle for this type of shooting is a Joe Pfeifer Sharps Borchardt in 220 Saunders Krag (a rimmed 22-250), stocked by Monty Kennedy in a beautiful piece of Oregon Myrtle, and superbly accurate. All this said I personally do not believe there is such a thing as over kill, dead is final, regardless of how you get there, a 22 rimfire or a Six Hundred Nitro.

We did indeed J. ,louis. And I might add they are getting harder and harder to find.