When you shoot your rifle's first shot on a clean barrel the projectile will hit in one point. Some rifles will shoot the second shot on a fowled barrel to a different place on the target. Sometimes this difference will be just a matter of next to nothing to almost three inches or more in some rifles. My Wolverine II will ususally shoot 1.5 inches higher with the first shot then the following shots.

For this reason, some people will dump 30 grains of powder down the barrel, stuff a cotton patch on top of it, and fire that off to fowl the barrel. Then they swab the barrel like normal. That way, all their shots will hit in the same place on the target because all shots are taken on a dirty barrel.

Others will shoot the first shot on a clean barrel and if that shot hits an inch to the left lets say, they remember that and adjust their point of aim for the following shots. Some sight in for the second, fowled shot and adjust for the first shot.

Try you rifle and see if there is a big difference. Then you can decide how you want to sight the rifle in. I personally sight in for a clean dry barrel. I only need one shot if all goes well.

Also some people claim that if you run a lubed patch down the barrel after you load your projectile on a clean barrel, that it will act like a fowling.. I do not know, I never like to put lube in the barrel unless it is on a conical or roundball patch...