A Sniper Rifle is a firearm designed to engage human targets with high precision individual shots at long range. When compared to assault rifles, they fire higher-powered ammunition, have greater range and accuracy, and tend to mount scopes with higher magnification, although their magazine capacities and rates of fire tend to be lower.
In the Battlefield Series, the term "sniper rifle" also encompasses designated marksman weapons, a class of rifles intended to lay down rapid, accurate fire at longer ranges than those at which the average infantryman armed with the average service rifle or carbine can be effective, but not intended to hit targets at the extreme ranges of which true sniper rifles are capable.
A Bolt-Action Sniper Rifle is a sniper rifle that utilizes bolts that are operated manually by the opening and closing of the action with a small handle, most commonly placed on the right-hand side of the weapon. In the Series, they are immensely powerful and capable of killing an enemy in one shot. Despite this, they tend to have a slower rate-of-fire due to their bolt-action design.
A Semi-Automatic Sniper Rifle is a sniper rifle that automatically extract a spent casing and load a new cartridge into the chamber after every pull of the trigger, resulting in a less powerful rifle with a higher rate-of-fire. Despite this, many utilize fire-limiters to balance the weapon.
Semi-Automatic Sniper Rifles are known as Designated Marksman Rilfes in Battlefield 4. Oddly, high-powered scopes (anything from x6 to x40 magnification), are not available for DMRs (they still have the Zeroing feature though, which suggests it's purpose of long-range shooting, but being limited to a maximum of x4, such as the ACOG).
Sniper Rifles typically have low rates of fire, meaning that each shot must count or the risk of wasting ammunition is present. When presented with multiple targets, the sniper should also decide the most valuable target and how it should be handled.
As with all projectile weapons in the Battlefield series, sniper rifle bullets are subject to gravity and travel at a specific velocity. In other words, they do not immediately hit their target as may happen in games that use the "hitscan" game mechanic.
Scope drift is a gameplay mechanic introduced in Battlefield 2 that replicates a soldier's breathing and the effect it has on aim. This results in the rifle's aim periodically drifting up and down, adding an element of challenge.
Drift can be reduced by crouching or going prone. From Battlefield 3 onward, a bipod can be deployed to eliminate drift at the expense of mobility.
To stabilize one's scope drift for a limited time in Battlefield 2142 and Battlefield 3, the Sprint key may be held. Battlefield 2142 requires the Gruber 5 Stabilizer attachment to be equipped.
Beginning with Battlefield 3, all weapons have a similar amount of drift depending on stance, but it is barely noticeable without a scope.
Battlefield 3 introduced scope glint, a gameplay mechanic added to high power scope attachments. A high power scope is defined as a scope with a zoom greater than 4x. This causes a sniper's scope to be visible from a considerable distance as a bright flare. The glare is brightest when seen from the direct line of fire and is less noticeable at off angles. This effect can be mitigated by either aiming away from the enemy (and using peripheral vision), switching to another weapon, or by switching to a low magnification optic or Iron Sights in customization.
Battlefield 4 scope glint will only be visible to someone within a 10 degrees viewing angle of the sniper.