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Fabricating and Installing a Taller Front Sight for a Ruger® Bisley Blackhawk®
by Roy Seifert

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Disclaimer:  This article is for entertainment only and is not to be used in lieu of a qualified gunsmith.  Please defer all firearms work to a qualified gunsmith.  Any loads mentioned in this article are my loads for my guns and have been carefully worked up using established guidelines and special tools.  The author assumes no responsibility or liability for use of these loads, or use or misuse of this article.  Please note that I am not a professional gunsmith, just a shooting enthusiast and hobbyist, as well as a tinkerer.  This article explains work that I performed to my guns without the assistance of a qualified gunsmith.  Some procedures described in this article require special tools and cannot/should not be performed without them.

Warning:  Disassembling and tinkering with your firearm may void the warranty.  I claim no responsibility for use or misuse of this article.  Again, this article is for entertainment purposes only!

Tools and firearms are the trademark/service mark or registered trademark of their respective manufacturers.

In my gun collection I have a stainless steel Ruger® Bisley Blackhawk® in .45 Long Colt with a 5 1/2“ barrel.  I have already accurized this gun so that all shots touch at 50 yards, added a wide-spur Blackhawk® hammer and checkered the spur, added a lanyard ring, polished the cylinder chambers, and modified the pawl to a free-spin pawl.  Refer to my articles:

I carry this gun when I go hunting and would have preferred a 4 5/8” barrel, but North Carolina requires a minimum barrel length of 5 1/2”.  I load this gun with my favorite hog load of 20 grains of Aliant 2400 under a 300 grain hard cast wide flat nose gas check bullet.  Unfortunately, this load prints about 4-inches high at 25 yards even with the rear sight in its lowest position.  Therefore, to lower the point of impact, since I couldn’t lower the rear sight any farther, I needed to raise the height of the front sight.

I read an article on the Beartooth Bullets web site where the author had the same problem with a Ruger® revolver on which he was working.  He silver-soldered a piece of brass onto the top of the front sight to give him the extra height he needed.  Since I have a hobby CNC mill at home I decided to fabricate my own higher front sight rather than modify the factory sight.  By designing my own sight I can create any pattern I desire.

Calculating the amount of increase in front sight height is a simple ratio and proportion problem.  For those who don’t remember your high school math I developed a Front Sight Height Calculator in Excel which you can download by clicking on the link.  The four quantities in the ratio are:

Change in Front Sight Height    =    Bullet Impact Change
Sight Radius                                Distance to Target

Because the change is in inches, all measurements must be in inches.  So what I had was:

Change in Front Sight Height     = X (this is what we’re trying to figure out)
Sight radius                            = 7.5 (front sight to rear sight)
Bullet Impact Change               = 4
Distance to target                   = 900 (25 yards x 36 inches)

Cross multiplying and solving for X gave me:

Change in Front Sight Height = Sight Radius x Bullet Impact Change / Distance to Target or 
X = 7.5 x 4 / 900, 
X = 0.0333

This change would work for the rear sight being at its lowest position.  To place bullet impact more into the middle of the rear sight adjustment I used a bullet impact change of 6 inches which gave me a change in front sight height of 0.05 inches.

My factory front sight blade measured 0.442” so I needed to fabricate a front sight that was 0.492”.  Brownells sells a replacement front sight blade that is 0.495” high so I decided to make my new blade to match that height.

I used a punch to remove the roll pin from the front sight base and removed the blade, then carefully measured it with calipers.

I used CorelDRAW® to design the pattern for my new front sight blade.  The height was 0.495” but I designed it with an undercut front to reduce glare, rather than a post or ramp.

I purchased a piece of brass 1/8” x 3/4“ x 12” from Online Metals, my favorite place to purchase metal.  I decided to fabricate the new blade out of brass because it’s easier to work with.  I realize that since brass is softer than steel the new blade could get deformed easier, but I’ve had steel blades get deformed by being knocked around, plus I can always make a new one.  I’m really not that hard on my guns so the brass blade should be just as durable as a steel one.  Plus, I don’t have to worry about finishing the brass.  However, I also purchased a piece of steel 1/8” x 3/4“ x 12” in case I wanted to produce a blade made of steel instead of brass.  I took the piece of brass, mounted it to a piece of wood on my milling table, and milled out the new blade.

After I milled the new blade I touched up the sharp edges with a jeweler’s file and installed it in the front sight base.  I took a 1/16” drill bit and using the hole in the sight base as a guide, drilled the roll pin hole in the new blade.  After I drilled the hole I installed the roll pin.

I didn’t quite make the front radius large enough so the front edge was pretty sharp.  I took my flat jeweler’s file and rounded the edge.  If I want it cleaner I can always change the design and make another blade.

A new, higher ramp-style front sight blade would have cost $10.00 plus shipping.  The two metal bars, brass and steel, cost me $15.00 including shipping so the hit to my pocket was about the same.  However, I can probably fabricate 18 to 20 front sight blades for the same price of one, plus I can experiment with different designs until I find one I like. 


   © Copyright 2010 Roy Seifert.