Rifle Sight Height Calculator

Rifle Sight Background

The traditional muzzleloading rifle has fixed, open, metal sights. This means that you have to select an initial height for both the rear and the front sights. Original longrifles had fairly low sights, at least the way we see them 200 years later. As a matter of standard practice, I set the initial height of my rear sights at 1/4″. That means that I must calculate the appropriate height for the front sight. Standard ballistics calculations allow me to determine height that will usually put me on the target at 50 yards, with the first shot.

Rifle Sight Adjustment

Then it is a matter of adjusting elevation by filing down either the rear (lower point of impact) sight or the front (raise point of impact) sight. Windage is adjusted by moving either the front or rear sight left or right using a drift punch on the sight base. I generally only move the front sight and only very slight adjustments are generally necessary.

The Front Sight Height Calculator

I used to just calculate the initial front sight of a new rifle on some scrap paper when it was time to install it. However, I decided it might be a good idea to permanently encode the calculations in a spreadsheet so I wouldn’t have to do the same calculations over and over again from scratch. I created my spreadsheet in Excel and saved it in the Excel 97-2004 format for greatest compatibility with various spreadsheet applications. You may download a free copy of the spreadsheet using the link below.

Click on the link below to download the file.

SightCalc2.xls

Using the Front Sight Height Calculator

Once you download and open the spreadsheet, using it is easy. You replace the values in Bold print. Everything else is locked. If you mount your sights centered on the flat with the front sight height as specified by this calculator, you should be pretty close, if not in the black, when you go to sight in. Of course, you do need a good idea of the muzzle velocity of your load. You can use the Lyman reference, but I don’t think you can go to wrong by assuming 1200f/s.