All my muzzys are sighted in on a clean, cool barrel. When I'm sighting in a rifle I usually have a couple guns with me. (usually do anyway as long as I'm going to be cleaning one I may as well get a couple dirty). This way I can load my rifle and keep it loaded for a week or two and not worry about corrosion setting in.
The one that needs sighting in gets fired then cleaned and dried and allowed to sit while I shoot something else. If you don't have that option, just wait a couple mins. and shoot it again after your sight adjustment. Doing it this way doesn't leave much room for error though so be very conscious of your shots. Make sure everything is the same including how you hold the rifle, cheek weld, etc. Also make sure your rifle likes that particular load and can shoot it well before you go making 1"-2" scope adjustments.