The more a rifle resembles a shotun's shape, that is, the face orientation to the sighting plane, the better the snap shooting accuracy will be.

This is the only rifle I have ever owned, bar none, that when snapped to the shoulder, the sights were dead on the target I was focusing on - every time - shooting offhand and snapping the rifle to my shoulder then firing immediately when the butt was pulled into my shoulder would bring a hit on an 8" disk at 50yards every time. This rifle never lost that 'duelling' competition on a swinging plate mechanism that made the other man's plate disappear when yours was hit.
My brother also found this rifle to work just about as well for him on that competition. Of course, when you are shooting against hooked butt Hawkens and 42" barreled longrifles, it was rather an easy competition to win.

The only other rifle that was close to the above rifle for fast firing fit, was a 1980-ERA Winchester M70 .264 MAG, that I re-barreled and chambered for the .458 Alaskan - it wore a 2 1/2X Leupold Scope, in low Weaver rings on Weaver bases - very low. The drop in the heel and comb were such that when snapped to the shoulder, the crosshairs would be within a 6" circle at 50yards, about 9 out of 10 times. The odd time, the 'shooter's' focus was off I guess.

Some rifles fit well enough to pull this sort of thing off, while most don't, without a lot of work and practice.

The more you practice with an individual rifle, the better the chance of teaching your body to do what is necessary to achieve this 'snap shooting' goal, one handy to have if hunting dangerous game, I'd think.