Good long range shooting requires both precision and accuracy. Precise shooting means, given the same input conditions, the rounds end up in the same spot. Accurate shooting means you’re aiming for the centre of your target, and accommodating for conditions. An accurate shot, from a precise rifle, strikes the centre of the target.

Caveat: I’m not writing from a position of authority. I picked up a new hobby, and writing short articles is a way to document my learning, and encourage further study.

Precision

The term precision is usually used when measuring something. It indicates the refinement in measurement, the degree to which you are measuring. For example, the number of decimal places in a number show the precision to which it was measured. If a mass is recorded as 10kg it only has 1kg precision, the margin of error is ±0.5kg. However, if the mass is recorded as 10.0kg it now has 0.1kg precision, with a margin of error of ±0.05kg (ten times more precise).

A precision rifle means it has been engineered at a high degree of quality, to minimise many of the variables within the influence of the rifle, that affect the trajectory of a bullet. Given the same conditions, a precision rifle puts rounds in the same spot, producing very tight grouping. For long range shooting there are three main aspects that affect precision.

Ammunition

Ammunition for long range shooting will have certain properties. The bullets are designed to have a high ballistic coefficient, meaning they are less affected by air resistance, retaining energy for longer (flying faster and straighter). Cartridges are developed to produce consistent muzzle velocity, helping produce a consistent bullet trajectory.

Rifle

Rifles produced for long range shooting will also have certain properties. The barrels will usually be longer, and heavier, with specific rifling to stabilise the bullet. Again, all intended to help produce a consistent bullet trajectory.

Shooter

The person pulling the trigger also has a significant affect on precision, probably the largest. The captain of the rifle club I joined put it quite eloquently, most problems come from the nut behind the bolt (if this joke escaped you, most precision rifles have a bolt action). You could put a high precision rifle in the hands of a novice shooter, and it wouldn’t do them much good. Their shots would likely still wander all over the target (if they land on the target at all). Whereas you could give a rifle of lesser precision to an experienced shooter, and they would produce good shots. Long range shooters invest a lot of time developing true aiming, steady holding, and excellent trigger control. They want to disturb the rifle as little as possible during the firing of a bullet, supporting the hardware as it does the job.

Accuracy

The term accuracy is also usually used regarding measurement. It describes the degree to which a measurement is correct - how close a measurement is to its true or correct value. Returning to the mass example again, if the true mass of an object is 10kg, then a measurement of 10kg is accurate - not very precise, but bang-on accurate. Another measurement of 9.997kg is both quite precise, and has a high degree of accuracy.

Accuracy in long range shooting means you are aiming for the centre of the target, and the rounds strike the target close to the centre. There are three main aspects that affect the accuracy of long range shooting.

Bullet trajectory prediction

While there are many variables that affect the flight of a bullet, gravity is the strongest. From the moment a bullet leaves a barrel it is being slowed by air resistance, and dropping due to gravity. Fortunately ballistics is a thoroughly studied field, and given measured conditions (i.e.: distance to target, bullet performance critera, and atmospheric conditions), the trajectory of a bullet can be reliably predicted.

Rifle zero

Zeroing a rifle is the process of aligning the sights such that, at a specific distance, your point of aim coincides with the point of impact, and your sights read zero adjustment - the bullet landed precisely where you intended. For the sport shooting discipline I pursue, rifles are zeroed at 300 yards (≈274m), creating a sight configuration that serves as a point of reference from which you can calculate further adjustments. If your sights aren’t high quality, or your zeroing isn’t done well, then every sight adjustment you calculate will amplify those errors, yielding inaccurate points of impact.

Wind assessment

While gravity only affects the vertical plane of bullet trajectory, wind primarily affects the horizontal plane. A crosswind will push a bullet left or right, a tailwind will carry a bullet (impacting slightly higher than expected), and a headwind will drive a bullet slightly lower on the target. Learning to read wind, and calculate sight adjustments to compensate for it so you can still aim at the centre of the target is a very valuable skill for a long range shooter. Similar to professional golfers who can read a green and make a perfect long distance putt, long range shooters will read the wind and adjust for it before taking a shot (only with an invisible medium that frequently changes). Reading the wind may involve various skills, such as observing flags, trees, or grass; or using a telescopic sight to perceive the mirage (that hazy shimmer close to the ground when you view something at long distance). It may also involve taking quantitative readings from devices such as a handheld anemometer.