Stumpkiller said:Don't disagree that it rotates around the line of sight. But unless your rifle can throw a curve it will be a different point of impact downrange.
We agree there. There certainly will be a difference in the point of impact, more or less, depending on the range and the degree of cant.
Heck, I see guys shooting their pistols held sideways all the time so I guess it works in the field.
Good suggestion, let's do that.
A look at the basics, using my smooth rifle, .600" ball, MV 1475 fps. Calculation shows that if I sight it in at 100 yards there will be 12.9 inches of true drop between muzzle and target, let's call it 13 inches.
If I point the bore at the X, the ball will fall 13" before it gets to 100 yards, and so will hit 13 inches low. So, I raise the barrel so it aims exactly 13 inches above the X, and now the ball drops exactly into the X. OK? Line of sight is pointed directly at the X, of course.
I find that it makes these problem easier for me to understand if I use the extremes, in this case near maximum cant. Let's turn the rifle 90° onto its left side, like those pistol shooters. Now when we shoot, we also rotate our head and line the sights up in the usual way, pointed right at the X. Now the line of bore is no longer pointed at a spot 13 inches directly above the X, but at a point 13 inches to the left of and perfectly level with the X. When we shoot, the ball goes where the barrel is pointed, 13 inches left. But, we originally set everything up that way to cancel out the drop. That no longer happens, there is no compensation for drop, so the full 13 inches takes place. The ball will now hit 13 inches left and 13 inches low.
The same happens if we tilt 90° to the right.
There is obviously much less effect if you only cant a little bit. Since drop comes into play in generating the error, the greater drop caused by longer ranges and slower balls compounds the problem.
Spence