This sight causes the rifle to shoot too low because not enough front sight is seen. Correspondingly, if more front sight is seen than ill.u.s.trated in the normal sights, the rifle shoots high.
c--Normal Sight. The following ill.u.s.tration shows the normal sight when the peep sight is used.
[Ill.u.s.tration]
The above ill.u.s.tration shows the correct alignment of the peep sight, front sight, and the bull"s-eye. The following features should be noticed:
1st. The top of the front sight and not the bull"s-eye is focused in the center of the peep sight.
2d. There is a thin strip of white between the top of the front sight and the bottom of the bull"s-eye.
3. Position and Aiming Drills.
Purpose: To so educate the muscles of the arms and body that the gun, during the act of aiming, shall be held without restraint and during the operation of firing shall not be deflected from the target by any convulsion or improper movement of the trigger finger or of the body, arms or hands. These drills must be taken daily, if they are to be of the maximum benefit. If you are enthusiastic about rifle shooting, and these drills are not give[C] to you, ask your company commander to show them to you, as they can be executed to advantage at odd times.
4. Deflection and Elevation Correction Drills.
Purpose. To show you how to raise or lower your rear sight, change your windage to the right or left, and note the effect on the striking point of the bullet in each case. In general terms these drills teach you:
(1) What to do when you are firing too high or low. (Elevation Drill.)
(2) What to do when you are firing to the right or left of the target.
(Deflection Drill.)
The a.s.sumption is in each case that the gun is properly aimed the instant it is fired.
Thoroughly to grasp every phase of the Elevation and Deflection Drills, it is best that you become familiarized with the dimensions of the following targets and the ranges at which each is used. It is not intended that you shall retain all these figures in your mind.
SLOW FIRE TARGETS
[Ill.u.s.tration: TARGET A]
This target is used during slow fire at 200 and 300 yards.
[Ill.u.s.tration: TARGET B]
This target is used during slow fire at 500 and 600 yards.
RAPID FIRE TARGET
[Ill.u.s.tration: TARGET D]
This target is always used with the battle sight at 200, 300, and 500 yards rapid fire. Battle sight is the position of the rear sight when the leaf is laid down, which is the habitual position of the rear sight leaf at drill. It is an open sight, and corresponds to an elevation of 547 yards.
WINDAGE
The rear sight is set on a movable base so that it can be moved to the right or left and the aiming point shifted accordingly in order to counteract the effect of the wind on the bullet.
General Rule. To shift the striking point of the bullet to the left move the rear sight to the left. And, of course, the reverse holds true when it is moved to the right.
A Specific Rule. One point of windage moves the striking point of the bullet 4 inches for every 100 yards you are distant from the target.
(One point of windage at 200 yards causes the bullet to strike 8 inches to the right or left of the line of aim; one point at 300 yards causes a 12-inch deflection of the bullet; one point at 500 yards a 20-inch deflection, and so on.)
ELEVATION
General rule for changing the elevation after hitting the target: A change of elevation either up or down, of 100 yards on your rear sight, will raise or lower your bullet in inches on the target equal to the square of your distance in yards from the target. I.e., a change of 100 yards in elevation on the rear sight leaf while firing at the 200-yard range raises or lowers the striking point of the bullet at the target 4 inches. A similar change while firing at the 300-yard range raises or lowers the striking point of the bullet 9 inches, at the 400-yard range it would be 16 inches, at the 500-yard range 25 inches, and so on.
The following ill.u.s.trations are self-explanatory in regard to windage and elevation changes and should be diligently studied during preliminary instruction. The effect of windage changes (given in points) will be found at the bottom of each target, while the effect of elevation changes (given in yards) will be found to the left of each target.
[Ill.u.s.tration: TARGET A, 6" x 4"
TARGET B, 6" x 6"]
The above system of indicating the windage and elevation on each target is used in the United States Marine Corps score book. Each man at Plattsburg, in 1916, was supplied with one of these score books. If used at the firing point they greatly simplify sight adjustments, besides containing other very useful information on shooting.
5. Gallery Practise. Purpose
1. To note errors in the position of the man while he is in the act of firing and call his attention to them after he has fired.
2. To give instruction in squeezing the trigger properly.
3. To stimulate and maintain interest.
4. Offers a check on what the man has absorbed from the other preliminary drills.
Fire just as much on the gallery range as you company commander will permit. You cannot fire too much. Every shot you fire should teach you a lesson on some point connected with the art of shooting.
SLOW FIRE
Following satisfactory gallery practise scores the men go on the range for known distance practice. Here the army rifle is fired with service charges at known ranges; first, for instruction if time permits, and then for record. To obtain satisfactory results the firer must perform correctly five essential things, namely:
1. Hold the rifle on the mark.
2. Aim properly.