Factors affecting long-range sniper.

First of all, the distance is the most important, so the pitch angle calculation of long-range shooting and trajectory becomes particularly important. The distance of 800 meters+,even if it is half an angle, will make the bullet deviate from the target. Secondly, the adjustment of wind bias is also very important. If not corrected, even the breeze will blow the bullet off the track. Temperature, the lower the temperature, the lower the impact point, the higher the temperature, and the opposite. Humidity, the higher the humidity, the earlier the trajectory drops, and vice versa. Altitude can actually be regarded as a combination of humidity and temperature, plus a little influence of air pressure. There is also bias current, and here we focus on bias current. Sniper courses in many American infantry schools only mention deviation, not in detail. I have seen many terrorists with broken left arms in Afghanistan, and most of them were injured by snipers. There is only one reason: army snipers love shooting long-range snipers, but they don't know how to correct drift. They usually aim at the chest, so the bullet hit the left arm because of the drift. Deflection means that the bullet deviates from the direction of rotation during rotation. Generally, it is not considered within 800 meters, and the impact within 1000 meters is also very small. As long as it is not accurate, it will generally not be corrected. On the contrary, at the distance above 1000m, because the bullet is close to the effective range, the flight speed is greatly reduced, but it still rotates at a high speed, so the influence is even greater than that of the wind, and it must be corrected by key calculation. However, for the 7.62mm NATO bomb, it is too much beyond the effective range, and it is difficult to control the drift. Deviation correction is only applicable to sniper bullets with a caliber of 0.338 inch Lapa or above. There is another one, geostrophic deflection. This is similar to the bias current, except that the object of force is not the bullet itself, but the earth. The left is in the southern hemisphere and the right is in the northern hemisphere. This is basically negligible, except that you have to hit a toothpick 2000 meters away …

Then there are subjective factors, such as shooting positions's shooting action when pulling the trigger, breathing frequency, whether the eyes are in the focus of crosshair projection when aiming (this can be corrected by lateral focusing, because most people's eyes are not so accurate) and so on.