I hadn't heard it put in quite the same terms as MJ and .38 Special put it in. However, I do figure a 4" circle at 100yds... anything within that circle oughta be well within punching a deer's lungs. 300yds though... that's making the shot a good bit tougher all the way around.
What I'm getting from this is, after four or five rounds putting my #2 tang sight dead on (busting clay birds) at 100yds as I did last weekend, I need to let it cool off a few minute and shoot it again. But whereas MJ's talking .303's, I'm talking .30-30 levergun. (I have a No.4Mk2 also, but the cold shot on it busted a clay bird at 100yds through the British-issue micrometer.) Maybe I should try to get a cold shot in with the Winchester this weekend and see. Usually though, if I get the sight dead on, it's still dead on the next range session with this particular rifle. Ya'll keep in mind MJ's talking scope with that Enfield sniper and I'm talking apertures with my .30-30 and Enfield both. Combine the cold barrel with the human element and the cone of probability widens somewhat.