Sighting in with a calculator

In the forum [Adjust your powder charge instead of your sights] I had mentioned that I was going to zero-in my rifle @ 50 yards using 45 gr. Pyrodex P. and I was going to grind .034th off of my front sight. The target below is the final product of my sighting in.

the formula for calculating your sight in is {your sight radius(in inches) divided by the range to the target(in inches)} multiplied by the inches between the center of your average group and the point to desire to zero.

Example: A GPR has a sight radius of 21 in. if you're target is 50 yards away that's 1800 in. if you're average group is 4 in. below the bull's-eye the calculation would be (21 divided by 1800)= 0.0116 X 4 in.= 0.0464 in change to the sights.

 

[musketman]

Behold, the power of math! :winking:

Thats some fine shooting...

 

Pioneer long rifles "Ham & Bacon Shoot" is May 1st and 2nd and I want to make sure I'm ready. During the matches, adjustable sights are taped so no one will adjust the elevation when changing the target ranges.

 

[Deadeye]

Military sights are calculated that way and I use it almost daily for pistols and rifles but I do it in a different way. I would devide 1800 by 21 and that gives 85.7 and tells you that for every 1/1000 you add or remove from your sight your group will move 85.7/1000 on the target, then I devide 4" by 85.7 and I get .0466 to be added or removed to zero. It's much easier than just filing and I can do it in the shop if I know the exact shooting distance and inches to move the group. It's amazing how few shooters know this.
Recently someone wrote to a magazine where a writer calls himself " the gunsmith" asked him about this and he said No, It's impossible, can't be done and a lot of other stuff.
He got lots of mail and later apologized. Brownell's and I think Track of the wolf has a chart in their catalog that shows this method.

 

Your right Deadeye it's just the basic formula to figure out your M. O. A. it doesn't matter if the point you are talking about its 100 yards, 50 yards or 20 inches in front of your nose