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or .... "SEEING YOUR WAY TO SHOOT AS THE YEARS ADVANCE"
We occasionally receive comment from those shooting that they no longer
enter the Service competitions using open sights because of a deteriorating
sight picture. It can be possible to become competitive again by dint of the
employment of an Orthoptic aperture. Put simply, this is a small disk with
an hole of about 1mm in it, fitted behind, or even in front of, your shooting
prescription lens. An adjustable pistol type iris may also be used, if such
can be located. If you have not done so already, this is really worth a try
for both small and full-bore use.
Did you think you could no longer be competitive over OPEN SIGHTS? If you still want to try, then read on...........
N.B. An orthoptic aperture is to be used only with shooting spectacles
It is NOT suitable (nor permissible) for use with a rifle that is already fitted with an aperture rear sight.
Modern target rifle disciplines, along with historic target disciplines in which aperture sights can be used, present few problems as long as you have a suitable pair of "specs" with a lens of your correct prescription. Shooting over open sights can be a very different matter.
When speaking to historic rifle shooters at fairs, meetings and over the telephone, reports of difficulties in obtaining a decent sight picture over open sights are all too frequent. We must reiterate the usefulness of an orthoptic. A simple thin 1" diameter disc drilled with about a 1mm hole and either used on its own, or placed in front of your shooting lens, will make such a difference that you will wonder why you never tried it before. Over 50 ? Then this could be for you !
Our natural desire to avoid overdoing shooting paraphernalia is laudable, but some of us now using these traditional and historically acceptable devices probably couldn't see the target without them! Give them a go......... I made my own in about half an hour by drilling a small aluminium disc and painting it matt black, but other adaptations can be easily achieved. Indeed, I have used a plain disc quite successfully for several years now.
Two images of such home-brewed arrangements are shown in the section below.
The following excerpt from "SHARPSHOOTING for WAR and DEFENCE" by W.W. Greener comments on the orthoptic, in this case with a six-hole aperture disc. His comment on alignment of the aperture with the sights was really only relevant to the designs of the day. Appropriate adjustment can nowadays quite easily be arranged.
" BLUR. - This occurs with all, and is very troublesome to most rifle shots, especially in certain conditions of light. On a bright evening with the sun behind one it almost disappears, but it is present under most other conditions of light. The inability of the eye to focus the sights and the bull's-eye at the same time is the cause of the blur. The reason it is not noticed with a perfect light from the rear is probably due to the fact of less light entering the eye obliquely.
For the same reason Orthoptic discs, or spectacles, assist in obtaining a fine "definition" of the sight. They consist of black discs covering the eye, through which small holes from .05" to .10" in diameter are pierced, their object being to cut off all but the
parallel rays from entering the eye. Orthoptic spectacles are undoubtedly of great assisstance, but the disadvantage gained by using them is somewhat discounted by the trouble experienced in aligning the aperture with the sights, so they are usually made adjustable in any position to overcome, as far as possible, this difficulty. They obstruct the vision of the shooting eye, and weather conditions cannot be so easily noticed."
This last point ignores the fact that without the orthoptic, many older shooters wouldn't even be able to properly see the target or the sights, let alone the weather and peripheral view!
Here is an example of a variable pistol-style aperture fitted behind a shooting lens. If this is not possible to arrange, then a simple thin metal or plastic disc, with about a 1 mm hole drilled in the centre, can be clipped or taped behind your shooting or everyday spectacles for a tryout.
Below is a 'Heath-Robinson', but effective, arrangement - made utilising radio-controlled model aircraft parts easily obtainable from any model shop. The plastic disc is more usually fitted to a rudder or elevator control-servo, and the brass and plastic links are the end links for the model aircraft control-rods, screwed together on the threaded section of a control-rod end. The disc has a Parker-Hale screw-in aperture just wound into the boss - a perfect fit - and enabling aperture size changes if needed. The whole can be swung away or removed if not required, and adjusted for position by rotating it on the eccentric pivot. A plain drilled disc originally carried out this task quite satisfactorily - even a drilled small coin would suffice.
The improvement in sight-picture seen over a "V"-notch and barleycorn or blade has to be seen to be believed.
N.B. Regulations obviously only permit the fitting of an orthoptic aperture to the spectacles - NOT to the RIFLE, where it becomes a rear aperture sight!
Some rifle shooters have been known to go to extreme lengths to improve their sight picture in this way; that is by combining an orthoptic aperture and their prescription lenses to obtain the ideal result. It is not for every body, but Les King is pictured, below, twenty-five years ago with his shooting specs. You should see the ones he uses to shoot the Miniature League Service class nowadays!
