by Phillip L. Atkinson and Orless L. Hickman
Anyone who has entered a buffalo aggregate or a light bench rifle aggregate knows that the matches that make up these aggregates consists of open sight and peep sight targets. Unless your rifle is equipped with removable sights, this means you must have two rifles--one with open sights and one with peep sights.
The major drawback with a one-gun system, however, is how to remove and reinstall the open sights in a quick and easy manner. When peep sights are being used, the open sights cannot remain on the barrel because they interfere. A number of shooters have come up with elaborate systems of removable sights, most of which require a milling machine or other expensive machinery.
As the photo shows, this sight base system consists of three parts: the base (3/8" square stock), the top or sight mounting base (½'' square metal tubing), and finally the sight itself. The sight used here is a Thompson/Center open sight with a square notch. However, just about any adjustable rear sight could be used.
The first step is the construction of the sight mounting base made of ½''square tubing. This tubing can be purchased at about any building supply store or good hardware store. Take the ½'' tubing and cut off approximately 1½''. The length of this section can vary according to the length of the sight that is used.
This sawed-off piece is then cleaned up with files and soldered to the underside of the roof created by the ``U'' shaped tubing. This will increase the thickness of the top layer, giving more support for the sight mounting screws. Two #31 holes are drilled in the center of this base to correspond to the hole spacing of the sight. They are then threaded with a 6-48 tap. The sight can now be secured to the top of this ``U'' shaped base.
After the sight base section is finished, the next stage is to make the base that attaches to the barrel and onto which the ``U'' shaped sight base mounts. This part is made of 3/8" solid square metal rod cut to the same length as the square tubing. To begin with, the 3/8" square rod should almost fit the open space of the tubing. With a little sanding on two sides it should fit very nicely.
Once these two pieces are made to fit together smoothly and with little ``play,'' they should be clamped together tightly. Two holes should be drilled through both pieces crosswise and parallel to the top with a #31 bit, and then tapped to 6-48. Two screws can be threaded through the holes, locking both pieces together securely. When these screws are removed, the top base and the attached sight can be lifted from the 3/8" square base. All that is left is to attach this square base to the barrel in the location most suitable to the shooter. This can be done with two 6-48 screws with their heads counterbored.
Once all parts fit together properly and the barrel is drilled and tapped to accept the 3/8" square base, the parts can be sanded lightly with #400 grit wet/dry sandpaper. After degreasing, they can be browned or cold blued to match the barrel.
Such a removable open sight system can be made in two to three hours. Also it can be made with
common materials and with everyday tools that most shooters should have. However, the main
benefit of such a system is that one does not need two riflesone with open sights and one with
peep sights. GOOD SHOOTING!
The photo above shows the complete sight base system mounted on the barrel. At left, all three
parts are shownsolid base, shaped sight base, and sight.