Bob,
I ran the "charging Cape buffalo" station on a practical hunting course for three years. The first year it was rapid shooting at stationary targets at different distances, but the last two years we had the target "charging" from behind a bush almost directly at the shooter--who had 6-7 seconds to get off as many shots as possible. Most people got off two, but a few very quick shots could get off three, and the best shots got off three in the "vitals." I saw just as many people jam controlled-feed rifles as push-feed rifles, usually by not bringing the bolt back far enough to eject the empty (short stroking).
According to shooting lore, this isn't possible, but after looking at the jams and doing a little thinking, I concluded the CRF jams could occur for two reasons:
1) The next round down in the magazine can still slide forward with the short-stroked bolt, either due to friction from the empty case, or:
2) The very bottom of the bolt face pushes the empty forward. This is rarer, but can happen in some CRF actions if the bolt is drawn just far enough back for the bolt face to end up behind the case head, but not far enough for the case head to hit the ejector.
On the other hand, empties from push-feed cases are ejected the instant the case mouth clears the front receiver ring. Thus the bolt doesn't have to travel as far back as in a CRF action for the fired case to eject.
The biggie in operating a bolt action is not whether it's PF or CRF, but bringing the bolt all the way back until it stops. People who operate a bolt by grabbing the knob sometimes don't bring it back all the way, especially when trying to hurry.
There are several ways to run a bolt, but the way I do it is the palm method. Instead of grabbing the bolt knob, I pull it back with my fingers cupped, palm up. When the bolt stops I reverse my hand and push the bolt forward, palm still open, with my thumb. It's impossible to short-stroke a bolt when using the technique, and it's also usually faster for most people, since instead of 4 motions (lift bolt knob, pull bolt back, drop bolt knob, push bolt forward) it's basically just a back-and-forth, 2-stroke motion.
I am not the world's fastest with a bolt rifle, but I shot the charging buffalo target as fast as anybody else did, even shooters who were using lever-actions. Sometimes that speed has come in handy in the field, including when I shot my only grizzly--with a push-feed rifle.
