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garryc
September 30, 2007, 08:49 AM
I installed a new rear sight on my EAA witness 45. With the new sight at it's lowest setting the gun shoots 8" high at 25yrds. As the current front sight is part of the slide, a dovetail will have to be milled. The rear sight is a Millet fully adjustable. How tall should the front sight be?

HammerBite
September 30, 2007, 11:08 AM
C = (S * E) / D

Where

C = amount of sight height correction needed.
S = sight radius from back of rear blade to back of front post, which are the surfaces you see while aiming.
E = amount of error. Vertical distance between point of aim and point of impact.
D = distance to target.


All distances in inches.

Shooting low -> front sight should be lowered.
Shooting high -> front sight should be raised.

See what your error is with the rear sight blade set about midway. You need to leave yourself some room in both directions for changes in range or changes in load.

Be very careful when ordering a front sight. The sight manufacturer might be measuring sight height from the bottom of the dovetail, or might not. When in doubt, pick up the telephone.

Michaelm45
September 30, 2007, 11:09 AM
http://www.brownells.com/aspx/NS/GunTech/sight.aspx

saands
September 30, 2007, 11:59 PM
How did it shoot before ... the Witness rear sights are usually really high (my only experience is with the fixed sight versions, so this may not apply). Anyway, because of this, I can't see how a replacement would be that much higher than the original ...

I hate to bring this up, but I know absolutely nothing about your experience level with pistols ... could it be the shooter? 8" at 25yds is a lot ...

Saands

Slopemeno
October 1, 2007, 12:08 AM
You could replace the rear blade only. Millett actually makes a pretty large selection of rear blade heights/notches, but dont offer all of them with the various bases.

I'd give Millett a call and see what they think.

garryc
October 2, 2007, 07:32 AM
You could replace the rear blade only. Millett actually makes a pretty large selection of rear blade heights/notches, but dont offer all of them with the various bases.

Unfortunatly, the lowest listed is .312 and that's what I have. So, when ordering the front dovetail blade do you add the depth of the dovetail?