Looking back over many a year of testing rifles and loads from a bench, I guess I would shoot a five-shot group in probably a minute between rounds, but no more than two minutes. Guessing.
I've seen a bunch of sub-MOA groups from one heavy-barrel Swift and several medium-weight sporters. .223, .243, .270, 7mm08 and '06.
I shot up a bunch of '06 ammo getting sighted in at my 500-yard range one day. Finally got dialed in, but was running low on ammo. So, two four-shot groups of 4" and then a no-dilly-dally ten-shot string. I had two called fliers before I even looked; eight shots in six inches. #2 profile barrel. Not sure what it proves, other than a medium-weight barrel didn't walk around on me very much.
I guess I figure that the advantage of a heavy barrel for target shooting is for long and fairly rapid strings of fire. But, I'm mostly a hunter and not a target shooter.