Several years, I had the honor to examine a " Slug gun rifle in cal. 69, shooting a 2-piece bullet, paper patched, that weighed 1760 grains, in front of 350 grains of 3Fg powder. Ignition was underhammer percussion, and the owner had a 46X scope of his own manufacture on the top of the heavy barrel. He had a copy of a target he shot at 500 yds., showing 10 shots in 5/26 inches, center to center. 7 of the hits were clustered together in the center of the bullseye. 3 other shots were clustered together, about 2 inches high and left, at 10:30 O'clock. There are two main causes of groups moving on the target. Since he didn't have the holes numbered to correspond to his shots fired, I asked him how much a crosswind affected his bullets at that long range.
He told me that until the wind gets above 25 miles per hour, he sees no effect on his POI on target with that massive slug.
That left the other problem that we shooter do, particularly if we see that we are shooting the best, smallest group of our life! Even with a scope sight- its easier to do with iron or peep sights- we tend to want to see that next shot hit, so at the release of the trigger, we change our focus from that front sight, to the target. That movement tends to make us lift our head just a bit, and away from our aiming eye. Ergo, the 10:30 O'clock POI for those other three shots. Left eye shooters will shoot to the 1:30 O'clock POI.
The cure is focus and follow through, as if you have to realign the sights and take a quick next shot. Its a mental game, but then so is operator error.
Some 20 years ago, now, I went into a slump shooting Trap with my modern shotgun. My good friend took me to the double range( 2 targets are throw with each "pull" called by the shooter, and you shoot both targets) where I instantly realized I was starting to dismount the stock from my shoulder before the shot was fired. I concentrated on follow thru, and my singles trap scores went right back up to the 23-25/25 targets I was shooting before the slump.
Its the same "sighting" Problem( we point shotguns at flying targets, not "aim") for shotgun shooters as you are having shooting the rifle. The solutions are similar, too. :thumbsup:
