Trajectory is of practical interest to hunters in several ways:—

(1). It shows the extreme range to which a given rifle can be sighted without letting the bullet rise more than a negligible amount above the line of aim; also the farthest range throughout which, without allowing for distance, it will neither rise above nor fall below a given animal's vitals when aimed at their center.

For example: I am hunting squirrels with a .22 taking the long-rifle cartridge. Squirrel range may be anywhere from fifteen to fifty yards. I adjust the rear sight, by targeting, to hit a nail head at thirty-five yards. The bullet's curve then will be as follows:—

(Table I). 35 Yard Trajectory Of .22 Long-Rifle

Muzzle velocity 1,100 feet a second. Top of front sight y2 inch above axis of bore.

The minus sign indicates drop below line of sight.

Trajectories must be figured from the horizontal plane, which is a straight line from center of muzzle to the point the rear sight is adjusted for. But the curve that counts in hunting is that above or below line of aim, which is a straight line from top of front sight to the same point. The amount of sight allowance depends upon height of front sight (axis of a telescope sight) and is proportional to the distance.

In this instance my .22 bullet, starting half an inch below line of aim, cuts upward through that line at ten yards from the muzzle, rises to a quarter-inch above it, then falls to line of aim at thirty-five yards. If I shoot forty yards with the same sighting, I must aim a quarter of an inch high, to allow for drop; at fifty yards, one inch high; at sixty yards, two and one-quarter inches high.

Can I improve matters by adjusting for a fifty yard " point-blank? " Let me see:—

(Table II). 50 Yard Trajectory Of .22 Long-Rifle

This curve is too high for squirrel shooting. The thirty-five yard point-blank was just right. For large animals, harder to approach, fifty yards might be the minimum.

(2). Such a trajectory table shows what allowance to make for drop of bullet beyond the point to which the sights are set. In making a quick shot beyond point-blank, one does not raise the rear sight. Either he draws a coarse bead, or he aims as much higher as he thinks the bullet will drop. The latter practice is best, for there is less guesswork about it.

(3. A set of trajectory tables for a certain cartridge, worked out for various ranges, shows how far it would be profitable to shoot at game of a given size with that charge—how far the bullet's curve will be low enough to give a reasonable chance of hitting. For instance: the .22 long-rifle cartridge will put ten consecutive shots in a three inch bull'seye at one hundred yards, or into an eight-inch bull'seye at two hundred yards? when the air is still.

Does this mean that it is fit to use at such ranges in hunting? Target shooters sometimes forget that there are no sighting shots at game. The precision required in judging distance with .22 long-rifle sighted for one hundred and two hundred yards, respectively, is shown below:—

(Table III). 100 Yard Trajectory Of .22 Long-Rifle

(Table IV). 200 Yard Trajectory Of .22 Long-Rifle

Everyone now and then makes a hit with the .22 at such ranges, but who keeps tally of the misses? Flukes are no proof of good marksmanship. No rim-fire .22 has a trajectory enough flatter than the above to make any material difference in shooting. Further comment is needless.

Let us examine the curves of some cartridges that are fit for serious hunting. The heights are given in inches and fractional parts:—

(Table V). Trajectories Of .32 Winchester Self-Loading Cartridge

(Table VI). Trajectories Of .30-30, Soft-Nose 170 Grain Bullet

(Table VII). Trajectories Of .30 U. S., Model Of 1906. Muzzle Velocity 2,700 Feet A Second

(Table VIII). 150 Yard Trajectory Of .30 U. S., With Sight Allowance

Top of front sight one inch above axis of bore.

The mean vertical deviation of the .30 U. S., 06, service cartridge should be added, proportionally, to the trajectories, in order to get the average height of shots that fly high, and subtracted for the average of those that go low, for no two shots from the same gun describe exactly the same curve.

This is a matter of importance, yet it is seldom taken into account. Trajectory figures are trustworthy, provided the gun and cartridge are steady performers; otherwise they are not. It is of little use to know the average curve of a series of fliers and drop-shots.

In the Forest and Stream trajectory test of 1885, a .50-95-300 rifle showed an average trajectory of 1.178 inches midway over the one hundred yard range. This was the mean height of five consecutive shots, fired from machine rest, through a paper screen at fifty yards. A .40-70-330 rifle, tested in the same way, gave an average rise of 2.452 inches at the same distance. If those averages alone had been published, most readers would have concluded that the curve of the .50 was much the best. But the shot-for-shot records showed that the .50-95 actually varied 4.29 inches vertically in those five test shots at fifty yards, whereas the .40-70 varied only 0.17 inch in its five shots.

This is an extreme instance; still, the difference in vertical deviation between popular cartridges of to-day is too great to be overlooked in this connection. Some will put a long series of shots into a four-inch bull'seye at two hundred yards; others will often miss a twelve-inch one.

Lieutenant Townsend Whelen, U. S. A., one of our highest authorities on modern rifles, has shown that the .30 Krag cartridge (commonly known as the .30-40), and others of the two thousand foot class, when charged with soft-nose bullets for hunting, will not make a sure hit at more than half the range that a .30 U. S. sharp-point will, the arm in each case being sighted to its farthest effective " point-blank " for deer, no allowance for distance being made in aiming. He adds to the trajectory of each cartridge its mean vertical deviation over the range sighted for, and this is the only fair comparison.