How to figure sight height

[hortonstn]

Is there a formula to figure sight height on a swamped barrel?

[shifty]

  Do you mean sight height for new sights on a new barrel or for sight corrections?

[Mr. Bubbles]

Measure the barrel width at the spot the sights will be installed, divide by 2. and that gives you your height above the bore center line at the barrel flat.  Do it at the rear, as well as the front.  When sighting in, I like to start with both fronts and rears at equal heights above the bore centerline, (on a rifle) which SHOULD put you low on the target when the ball hits..  Then you can at least adjust your L-R alignment, and develop your optimal load.  It's easier to file material off the front blade than it is to add it.

With a pistol you might want to have a higher front sight than the rear, because recoil may flip the muzzle more by the time the ball exits.

[Daryl]

Perfect - equal height for rifle to start, 1/10" higher front for a pistol. With some rifles, this will give a 25yard zero right off the bat.
 I have never seen one shoot high with starting equal height - that I can remember, that is.

[Mark Elliott]

I made a Excel spreadsheet that calculates the front sight height.   It works well assuming you guess pretty close on the muzzle velocity.    Here is a link to the spreadsheet on my web site; http://markelliottva.com/wordpress/wp-content/uploads/downloads/SightCalc2.xls.   

[Jerry V Lape]

Great information regarding sight height.  I would like to know what point on the rear sight you are measuring?  Would that be to top of the blade, bottom of the notch or what? 

[Mark Elliott]

For my purposes, I am measuring from the top flat of the barrel to the top of the notch, where you are aligning the top of the front sight.

[lost arrow 801]

Hello my friend. I asked a similar question once and the advice i got was "Start high and file it down until it suits you".

[Mark Elliott]

I prefer to be almost in the black when I fire the first shot.    My spreadsheet normally gets me there.   I don't like doing a lot of filing at the range.   I think it makes other shooters nervous.   

[Eric Krewson]

This is the basic idea, that said, I make them tall and file them down because I never know what load I will be shooting in a new gun and need some wiggle room for front sight adjustment. 

[Daryl]

When Taylor is finished a new rifle and it's time to test, I like to go along. An extra set of hands is handy for holding the gun down while he takes a

few draws of the file. That is usually all it takes when the sights are set level, front and back, above the bore's centre line.

[shootrj2003]

Thank you mister bubbles,that is simple and to the point with no complicating math and trig, jargon thrown in to impress people .that is all I needed thanks.

[arkeliet]

Calculator to find out how much the sight needs to change in side or height in this adress: https://skydeselskabet.net/tools/siktejustering.php
Its made in metric units and in norwegian.
The formula itself is:
 ((line of sight in cm*deviation in cm)/shooting distance in meters)/10

Translation
Length of line of sight  in centimeter   =       Lengde på siktelinjen
shooting distance in meter                 =       Skyteavstand
deviation at target  in centimeter        =       Avvik på skiven
gives you Millimeter correction of the sight    = Millimeter korrigering av siktet

[bobw]

The original question has been answered but sight correction come into question sometimes.  The post before this one has a correction in metric.  This is an easy sight correction calculator I use in inches.

http://www.sdmfabricating.com/sightcalc.html

[Steeltrap]

The original question has been answered but sight correction come into question sometimes.  The post before this one has a correction in metric.  This is an easy sight correction calculator I use in inches.

http://www.sdmfabricating.com/sightcalc.html

Appears to be over simplistic as the weight and velocity of the projectile comes into play. This website has no input for either.

[Daryl]

A mathematical formula cannot tell you how to "install" sights to hit centre at a given range, whatever your choice of that might be.
It is an easy job to install all ML sights dead level, measured from the centre of the bore to the top flat of the rear sight and top
surface of the front blade. If a bead sight is used, then the centre of the bead is the 'top' measurement.
If installing a bead or sugar loaf sight on the front of the rifle, then the rear sight should be made higher than the front sight, so it
must shoot high and then can be filed to produce centre hits at the intended range.
This is not rocket science.
If the front sight (blade front) is initially made the same height as the rear (above the centre of the bore), it will either shoot centre
at 25 yards, or will shoot a tich low. It is an easy job then to simply file off a bit and re-shoot.
IF and this is a big IF, the gun shoots high with level sights, then the bore is not in the middle of the barrel, or if appearing centered,
it is angling up to centre from below centre to appear that way at the muzzle. Either way, the gun will shoot high. Simply taking some
off the rear sight will remedy this situation.

[bobw]

The original question has been answered but sight correction come into question sometimes.  The post before this one has a correction in metric.  This is an easy sight correction calculator I use in inches.

http://www.sdmfabricating.com/sightcalc.html

Appears to be over simplistic as the weight and velocity of the projectile comes into play. This website has no input for either.

LOL, Yes it is, a simple calculator for a simple guy like me!
It’s not a ballistic calculator, it’s a sight adjustment calculator and is only intended to be used with a consistent load, usually after working a load up.
For example, I have a gun in my shop that is shooting a nice tight group, 2 1/2 inches high at 50 yards.  It has a rear peep sight that is adjusted as low as it will go.  The front sight is a bead that can not be modified.  So I either need to make a new front sight or try to find one that will work that is the correct height.  In either case this calculator help get me in the ball park, from where it it currently is, where I can get more adjustment out of the rear sight.
Hope this clears up how this is used.
Bob

[Daryl]

Simple. A bead sight, 1 1/2 bead diameters higher than currently on the rifle should have you shooting slightly low, maybe an inch or so at 50 yards.

[Steeltrap]

Well, I guess if my rifle is shooting “X” high at “X” yards, and the rear sight can’t go any lower, then I have to make a new, higher front sight. So, I do that and make the new sight 1/4” higher.

Off to the range and a few shots show I’m shooting low. A few file strokes and I’m still low, but higher than the first time. After half a dozen shots I have it pretty well wired in.

And that was even “more simpler” than the “sight height calculator”….and it’s spot on.

[Daryl]

1/4" is a lot  but much depends on bl. length. The longer the barrel, more must be added or taken off to make much difference.