The way I did my last rifle was I went on morning and fired a shot at 100yds. I moved the reticles to point of impact. I put the gun up afor a few hours. Went back fired another shot and adjusted the scope. Put the rifle up for about an hour and moved out to 200yds. Fired a shot. Made adjustments. Waited another hour and verified the 200yd zero. Now I have my own range here at my house so I could do it that way. I would personally give a minimum of 30mins between shots if I could. However my new Tikka will shoot the same point of impact with a cold barrel as it does after 5 shots. I know this because I checked it on several occasions. My lighter weight Savage 110 with the thin barrel will walk after a couple shots. Not much but it does. No fouling shot or cleaning of the barrel when I did mine. I’m not saying this is the right way to do it, I’m saying this is how I did mine.