If the wind is blowing straight down the range from the targets, it will naturally increase the resistance for the bullet. Also, by retarding its speed the trajectory will be lowered, thus causing the shot to strike below the spot aimed at. To counteract this the aim must be taken higher, but the rifle is so constructed that by raising the slide of the backsight a little, aim may be taken at the original spot.
When the wind is blowing towards the targets, from the firing point, it has little or no effect upon the bullet, as the speed of the latter is so much greater than that of the wind. A side wind will slightly alter the elevation of the bullet, in a ratio to its strength.
Most good shots agree that it is safer always to take up the same amount of foresight into the alignment; as by taking a large foresight at one time and a small one at another, one is apt to get confused, especially when other matters have to be considered at the same time. But it must also be remembered that the different degrees of the light's intensity have a marked effect upon the appearance of the foresight, and must be allowed for. If the light is very dull, the foresight will not be very distinctly seen; and, unconsciously, more of it will be brought up. This has the effect of bringing up the muzzle end of the rifle, and of giving the bullet a higher trajectory, thus causing the shot to strike high. But, on the other hand, if the light is bright the foresight is easily seen, and less of it is unconsciously taken up, so causing the shot to drop. These differences in the appearance of the foresight are corrected by raising the backsight in a bright light, and lowering it when dull.
Mirage and refraction are very troublesome matters to deal with, for the bull's eye appears to be where in reality it is not. And it is almost impossible to ascertain the allowances which should be made for this source of error without the advantage of a trial shot.
The condition of the atmosphere as to temperature and humidity has much to do with the fouling inside the rifle. In hot, dry weather it is apt to get hard and dry. After a few shots have been fired, it cakes and fills up the grooving of the rifle. Consequently the amount of the spin of the bullet is affected, often causing the shots to drop, and spoiling all chance of accurate shooting. This can be avoided by blowing down the rifle after each shot, when the moisture of the breath will greatly improve the condition of the encrusted barrel. Many rifle shots have indiarubber tubes for this purpose, and blow down the barrel through them from the breech end. Some competitors even take more trouble; for, after each shot, they shut the breech, and get up from their position in order to blow down from the muzzle end. This method involves more exertion, but it is evident that any moisture blown down with one end stopped, and thus permitted to accumulate, must of necessity be more effective in cleansing the barrel.
In warm, damp weather, the fouling becomes moist and greasy, letting the bullet slip through easily. These differences in elevation caused through fouling can also be allowed for by altering the elevation on the rifle between the shots.
An ingenious little instrument called the Vernier is used for measuring the elevation, When it is considered, that, at 600 yards distance from the targets, the difference of 1/150th of an inch on the backsight will be equal to half a foot on the target, it will evidently be of the greatest importance to be able to adjust the sights accordingly. For this purpose Verniers are made so delicate as to move the backsight through such a small space as the 1/150th of an inch at a time. By this means of adjustment, should a shot strike straight above the bull's eye, you have only to notice the exact amount of the error in inches, and then the elevation can be lowered 1/150th of an inch, or a "degree" as it is called for every six inches the shot is above the mark; provided always that the other conditions are the same as before.
Theoretically, wind is far more easy to deal with than elevation; for, if the wind blows across the targets from the left, it would naturally drive the bullet to the right. Therefore, by aiming in the direction the wind is blowing from, proper allowance can be made. The difficulty lies in the practical part, i.e., of judging exactly how far the bullet will be driven from its true course. Practice is the only possible teacher in this matter; and it is wonderful to see how some experienced shots will estimate the strength of the wind, acting only on their own judgment, and succeed in hitting the bull's eye at first shot, and especially when we learn that at 600 yards as much as fifteen feet of windage is sometimes required. But at times there seems to be a certain amount of chance attached to the "finding of the bull's eye." I have heard of a competitor who had fired several shots and could not find the bull's eye. He was firing in a competition called "Cartons," in which the most central hit takes the highest prize. After several unsuccessful shots, he wished to alter some part of his rifle and for this purpose turned it upside down. In doing so he accidently pulled the trigger. This turned out to be a singular instance of good luck, for the shot not only was fired without harming anyone, but actually hit the very centre of the target! This undesigned shot proved to be the best Carton of the meeting, bringing the competitor a prize of several pounds. I have often heard it said on the range that "there is no luck in shooting except bad luck;" and it certainly is very disappointing to lose several points in a competition before you succeed in finding the bull's eye; but it is still more disappointing, when, having found it, the wind keeps changing its force or direction, and so increasing your perplexity. The only consolation in this disagreeable experience is, that a great deal more is learnt from one bad score under these circumstances, than from many good ones made with a steady wind.
All my remarks have referred to target-shooting only, in those cases where competitors are not hurried, but can take their own time to paint their sights and adjust them with "machines," carefully marking the allowance for windage on their sights, so that they may aim at the bull's eye every time, and have no more to think of but holding the rifle steady. I use all these helps myself, finding them a great advantage; and I believe that studying all these minute but necessary particulars is a good training for those who may have to use their rifles for more serious purposes than competing for prizes at rifle meetings. For, although in practical shooting they will be obliged to use the rifle just as it is served out, they will prove themselves to be experienced shots, and know how to handle their weapons with that skill which is always the result of careful training and practice.
Winifred Louis Leale.