A back-up position selected by a sniper to which he can displace and still shoot into his original Sector of Fire
Avenue of Approach
A road, path, or open area across which the enemy could advance toward you, depending on whether he's mounted or dismounted. Snipers should cover dismounted ones.
Back Azimuth Detection Technique
A technique to identify an enemy sniper's position by inserting a cleaning rod or dowel into his bullet hole and noting the trajectory from which it was fired.
Any material through which your rifle's bullet will not pass located behind target to manage friendly fire risk.
A concept whereby a sniper should seek engagements only when he's at least 400 yards away from his quarry and beyond the effective range of the enemy riflemen.
A rating system based upon a bullet's weight, shape, and ability to retain velocity. The higher the rating, the higher the bullet efficiency at long range.
An old sock or small cloth bag filled with a dry material such as sand and placed below a rifle butt's heel so it can be squeezed to lower or elevate the rifle for precise aiming.
A two-legged support attached to the rifle forearm for better stability. It should never be attached to the barrel.
An aerodynamic bullet design shaped like a boat, with a pointed tip and gradually tapered to a flat base. Have better long range accuracy than other bullets.
Various kinds of vests designed to protect wearers against injury from fragmentation and small arms fire.
An optical device inserted in a rifle muzzle to tentatively zero a riflescope by setting its crosshairs coaxial to the rifle's bore. Speeds up subsequent live-fire zeroing.
The ballistic measurement of how far a bullet drops, at 100 yard intervals, were the barrel pointed perfectly parallel to the Earth. A baseline trajectory used for computing other ballistic data.
Bullet Drop Compensator
A knob mounted atop a riflescope by which the shooter can adjust elevation without rezeroing the weapon so that he can fire quickly at varying distances and aim directly at target instead of "holding."
Also called "bullet track." A tiny but visible wisp of trail left through mirage by a bullet's shockwave.
Calling a Shot
The practice of "calling" where your shot impacted just after firing but prior to observing it through a spotting scope.
Turning or dipping the barrel slightly right or left, usually as the result of a bad sight picture or improperly mounted scope. This results in bullet trajectory obliquely departing from Point of Aim as distance increases.
Catastrophic Brain Shot
A special one-shot-kill to the brain stem or neural motor strips which kills so instantly that body reflexes cannot react.
Ammunition which detonates by striking an exposed primer in the center of the cartridge base. Used in all military and big-game rifles.
Cold Barrel Zero
Applies ONLY to the exact impact of the very first round, not after warming. Police and counterterrorist forces zero their weapons for the CBZ.
Expressed as full MOAs or 1/4 MOAs, you must "come up" in elevation to go from one range to another range, usually in 100-yard increments.
Bushes, ditches, etc., that offer concealment from observation, but not always protection from fire. Ideal route to a sniper's hide should have both cover and concealment.
Various techniques and tactics to eliminate a sniper, or at least limit his effectiveness, ranging from blinding him with smoke to firing a wire-guided missile at him.
Buildings, thick trees, etc., which offer protection against small arms but not always concealment.
Tracking term meant to cut back and forth across a quarry's likely route until discovering "sign" of his passage.
A countersniper technique that attracts an enemy sniper's fire so as to locate his position and eliminate him.
The ability of one eye to focus more intensely than the other, causing the second eye to compensate by slightly misaligning itself.
Doping the Wind
A competitive shooter's term, meaning to estimate the wind accurately and adjust sights for correct compensation.
A heavily camouflaged rifle case dragged behind a low-crawling sniper in a Ghillie Suit so he has both hands free for picking his way through brush.
The amount of potential energy a bullet can deliver at various distances is expressed in foot-pounds.
A standard series of steps a sniper takes from the instant he detects a target until he fires. This is practiced to ensure the sniper has taken into account range and wind and prepared himself for likely 1-shot kill
The cone of clear vision created at the rear of an optical device, such as a spotting scope. Measured by dividing the objective lens diameter in mm by the magnification.
That portion of a bullet's travel after it exits a muzzle but before impacting a target.
The distance between a shooter's dominant eye and the rear (ocular) scope lens from which he can clearly see the entire scope field of view. Usually 3 or 4 inches.
The deceptive technique of creating the impression you are where you are not, or intend to travel a route that you actually will not use.
Field of Fire
An area relatively free of obstruction into which a sniper can fire, ideally up to the maximum range of his weapon.
Field of View
The angular measurementof how wide an area can be observed through an optical device. Spotting scopes have a very narrow Field of View, rifle scopes wider, binoculars even wider.
A target that only exposes itself for a few seconds, then disappears and reappears. For both police and military snipers, this is the kind of activity a target will most often display.
A barrel on which thin grooves have been cut along its outside, long axis. Allows for a greater external surface for cooling while also creating better rigidity.
A shooter's continuous concentration and nonreaction after firing a shot so he develops a mental and physical habit of no disruption at instant of shooting.
Bullet design intended to completely fragment upon impact and thus impart 100 percent of energy into the target. Devastating on soft targets.
Most commonly seen frangible bullet
Glaser safety slug (manufactured as both rifle and pistol cartridges)
Barrel which does not touch the rifle's forearm, for better accuracy. It "floats" freely, unimpeded, with a 1/8-inch clearance recommended.
Technique of heavily sandbagging a rifle and touching it only with your finger when firing to improve consistency.
Elaborately camouflaged coverall originally used by Scottish gameskeepers to catch poachers, adopted for use by snipers. Covered with fake brush; makes sniper almost invisible.
Applying liquid fiberglass or epoxy between a rifle's action/receiver and the stock for the snuggest possible fit. This eliminates any "play" between action and stock. Used in quality sniper rifles.
The undesirable practice of stretching one's head up above the rifle cheekrest (and thereby losing the stockweld) in order to see through a scope. Corrected by using a different buttstock, installing a strap-on cheeckrest, or using an adjustable cheekrest.
Ground surveillance radar vectoring
Using friendly radar to detect enemy forces in darkness, then maneuvering night vision equipped friendly snipers either into position to engage the enemy or around the enemy if his forces are too numerous.
Also called "full metal jacket" or "metal case" this bullet design uses a hard metal covering over a lead core so the round does not expand upon impact, as required by the Geneva Convention - all military ammunition is this.
The temporary or permanent position a sniper occupies to engage a target. Depicted on a map as a triangle with a scope crosshair inside.
A good hide should have
excellent concealment and cover, good observation, Fields of Fire, and a "backdoor" through which the sniper can invisibly displace to another hide position after engaging.
A term that distinguishes more powerful rifles from .22-caliber rimfire weapons. All big-game and military rifles are high-powered.
Compensating for wind or elevation by purposely aiming high/low or right/left instead of changing the setting on your scope. This is the fastest means of engaging multiple targets at assorted distances.
Bullet design in which a cavity has been reamed in the tip so that upon impact it dramatically expands, increasing the delivery of energy to a target - similar to softpoint.
Desired effect of a bullet fired during a hostage rescue operation so that the subject instantly is incapable of firing a weapon or otherwise endangering anyone.
A night observation device which needs an infrared light for illumination (active). These lights can be detected by other IR optics as well as Western Starlight-type night vision devices (passive), making them dangerous to use.
A vintage American frontier term, meaning to hold rifle sights right or left of a target to compensate for effect of a crosswind.
The side width of a human body--about 12 inches--used to estimate how far a sniper should lead a moving target. Ex: at 500 yards a sniper must aim two Leads ahead of a walking man and four leads ahead of a running man.
The smooth, unrifled gap in a rifle's bore between the chamber and the start of the rifling. A sniper-quality weapon should have a leade that's so short that the bullet need not "jump" into the rifling, since this degenerates accuracy.
The misstated ability of a lens to gather available light, an important factor for dusk/dawn and night shooting. What it actually refers to is light transmission through the lens, which is determined by how wide the objective lens is, how finely ground is its surface, and the quality of its lens coating.
the amount of time between the sear releasing the firing pin and its striking a cartridge's primer. Short lock time is desirable for a precision rifle so that there's no time for weapon movement after the shooter pulls the trigger.
Lot or Lot number
One batch of ammunition made up at the same time and using the same run of subcomponents. A sniper uses ammunition of the same lot number to enhance consistent performance.
A comfortable "tree seat" developed in India for tiger hunting that uses straps and ropes lashed between tree branches.
countersniper technique first used in WWI in which all of a unit's weapons are fired simultaneously for one minute at any possible position a concealed enemy could use.
ammunition manufactured to much closer tolerances than regular ammunition to produce rounds that consistently perform to the highest of standards
Maximum effective range
The greatest distance at which a weapon can inflect casualties, based upon both the energy of a bullet and the weapon's inherent accuracy.
An angular measurement equal to 1/6400 of a circle or 3.375 minutes of angle. The mil is a handy measurement since it subtrends 1 yard at 1000 yards and therefore facilitates range estimation.
A tiny dot of very exact angular width in some scope reticles, such as the M3A1 Leupold, and used for range estimation.
The area along a ridgeline just below its actual crest, preferred by military units for occupation or movement because soldiers will not be silhouetted against sky.
Minute of Angle
An angular width normally used to describe shooting and scope adjustments since 1 MOA almost exactly equals 1 inch at 100 yards, 2/200, etc.
AKA "base," this is the intermediate adapter which connects a scope to a rifle. Should be of machined steel and use hex screws. Scope rings attach the scope to the base, and should also use hex screws.
A recoil-reducing device attached to the barrel that deflects blast down or backwards to 'pull' the rifle slightly forward. Reduces recoil but also makes blast more visible.
Polished, smoothly finished rifling at the muzzle done during manufacture to ensure the unimpeded, consistent exit of bullets. Some have a recessed crown to reduce the chance of 'dinging' any rifling edges during normal use.
A bullet's speed when it leaves rifle's muzzle, in FPS. Speed declines during flight as does energy.
A term applied to ammunition and certain firearms to distinguish them as having been modified for higher precision shooting. Expert gunsmiths have fine-tuned them for match-type accuracy.
Natural line of drift
the route human beings most naturally would take from place to place. Usually parralel to streams, down middle of valleys, enemy soldiers walking slightly inside woodlines and crossing danger areas at narrowest possible points.
Night observation device
Any of many night vision sights and scopes that intensify light to 'see' in darkness. Initially called 'starlight' scopes. Also termed 'passive' devices since they don't use infrared.
No fire area
An artillery fire planning term, meaning an area in which no fire may be placed without the permission of the unit which created it.
How sniper teams use NFAs
To create safe havens in their area of operations, for forward observers or aerial observers can call artillery or airstrikes on sudden targets without timeconsuming coordination.
Operation Order (OPORD)
A written order following a 5 paragraph format that addresses situation, mission, execution, service support, and command and signal. A commander issues an OPORD to subordinates to ensure all are executing his common plan, with internal coordination.
The max. height above a horizontal surface that a bullet rises while in trajectory to a target. Ex: the ordinate of a federal .308 match round that impacts a target at 300 yards is 7.23 inches.
The tendency for scope crosshairs to shift and change the point of impact if the shooter moves his head. Not a problem with new quality scopes of 10x or less, but can be a problem above 10x unless objective lens is adjustable.
Permanent wound channel
The path of permanent tissue damage left by a bullet, usually an inch or 2 in diameter. When this channel passes thru vitals organs or nerve tissue, significant injury or death results.
Exploiting the flat phase of a particular bullet's trajectory so a shooter can hit targets with almost no high or low holds.
Ex. of point blank range
Federal .308 match does not begin plunging until 400 yards; therefore, setting scope at 300, the shooter can ignore correct range estimation and holds, instead aiming dead-on at all ranges to 300 and never miss by more than about 7 inches--acceptable for hunters but not snipers.
The correct practice of firing from 1 of 4 positions for max. stability and best accuracy.
Commercial rifle loads of closer tolerance and therefore closer to true match grade loads than typical ammo.
The hide a sniper initially uses in a deliberate defense, from which he can engage targets in an assigned sector of fire.
2 more positions after primary
"Alternate" and "supplemental" - can displace to after firing from primary.
An optical/mechanical device to determine the range to a target, which which there are 3 basic types.
3 types of range finder
two lines in a riflescope
(also laser but expensive)
Term used by FBI to describe the need for a bullet to disable a suspect quickly so he no longer can resist apprehension or pose a threat.
Rate of twist
Term to describe rifling by the distance in inches a bullet passes in the barrel during a single rotation.
A wide, heavy steel lug attached below the barrel at the front of the receiver through which recoil is transmitted to the rifle stock.
Why the contact between lug and stock must be true and snug
to ensure action and barrel do not twist during recoil.
Recon by fire
A countersniper technique in which friendly snipers fire several rounds into the most likely enemy sniper hides in hopes of hitting him by chance.
Typical result of recon by fire
Merely suppresses sniper or causes him to move without eliminating him. Depending on situation a commander could call for a "mad minute"
Term describing the ability of an optical device to transmit light. Is computed by squaring the exit pupil.
The point along a route at which a subelement or accompanying group leaves the main body to follow its own route.
Remotely monitored sensors emplaced by hand, air, or artillery. Can be used to maneuver snipers into an engagement of enemy at night or in areas not otherwise observable by friendly forces.
Usually found only in .22 rounds, a cartridge that has an internal primer detonated by a firing pin striking the cartidge's rim.
A high-powered rifle cartridge whose base is no wider than the cartidge's side, a design which facilitates feeding into the chamber - US and NATO rounds are rimless.
A cartridge, most often .22, whose base is wider than its side, which simplifies extraction.
A bullet design presenting the max. width of the bullet to a target upon impact, imparting greater "knock down power" or energy.
Disadvantage of round-nose bullets
Lose velocity quickly and drift in crosswinds, with a resulting decline in long range accuracy.
Sector of fire
An assigned area into which a sniper places his fire. Usually this is a portion of a wider field of fire, but is sometimes as wide.
A bench or table constructed so a sniper can fire prone through an upper-story window from deep inside a room.
Specially trained marksman equipped with quality optics and a target grade weapon who employs stealth and fieldcraft to engage targets at ranges greater than those of the conventional rifleman. Due to equipment and observational training, excellent info source.
Obsolete term for a suppressor, no longer used because no device totally silences a firearm.
Sniper data card
A detailed record of ballistic data, developed and periodically modified, on the performance of a particular sniper rifle while used by a particular sniper. Enables sniper to know his weapon intimately, understand performance in all weather conditions, ranges, and targets.
Sniper demolition ambush
A remote controlled, command detonated ambush using a series of claymore mines aligned along a route likely to be used by the enemy. The sniper detonates the Claymores using a single long-range rifle shot.
Sniper observations sector
Sector assigned exclusively to a sniper team for independent operations and marked on maps by a thick border with SOS on each side. The sector's usually about a 3 to 5 kilometer square, large enough for the team to stalk, hide, engage, and evade.
Sniper range card
A detailed sketch of a sniper team sector of fire, including all prominent terrain, likely enemy avenues of approach, cover the enemy may use, and dead space, with range estimates so the sniper can engage targets quickly.
Sniper skirmish line
An assigned line on a map showing that a sniper team may manuever up to 1 kilometer from it while stalking, hiding, shooting, and evading. Depicted as a jagged line ending in arrows, similar to a Reconnaissance Screen.
Usually a two-man team of qualified snipers, with one man acting as spotter while the other snipes, and rotating responsibilities. Team composition could vary by mission and Military Table of Organization and Equipment.
Also called "dum dum" bullets, this design uses an exposed lead tip which expands upon impact, this increasing the amount of energy delivered to the target for more damage. Outlawed by geneva convention for combat use, but legal in domestic counterterrorist and criminal situations. Softpoints frequently are preferable because they more quickly dissipate energy and fragment, lessening danger to bystanders.
Using the cover name "studies and observatory group," this was the US military's top-secret unconventional warfare task force during the vietnam war, composed mostly of US Army Green Berets used in cross-border intelligence forays and raids into Laos, Cambodia, and North Vietnam
A trained sniper and member of a two-man sniper team who helps the sniper detect and identify targets, then adjust his fire on the target. He's also responsible for close-range security.
A single-lens scope, usually of 20 power or greater and used with a tripod for long-range observation, adjusting the sniper's fire, and reading mirage for wind speed and direction.
The ability to move silently and invisibly, which incorporates camouflage, selecting the best route to a hide, physical fitness, and self discipline.
The habitual placing of a shooter's cheek at the exact same spot on his stock, shot after shot, so that his eye relief and scope picture become consistent. By "welding" his eye to one spot, a rifleman improves consistency and therefore accuracy.
The amount an angular measurement equals at a given range. For example, 1 minute of angle subtends 3 inches at 300 yards.
A sniping hide to which the sniper may displace after firing from his primary or alternate positions. Unlike the alternate position, the supp. one does not allow firing into the primary sector of fire; from a supp. position, he shoots in a different direction/SoF.
A device that uses baffles and fine meshing to dissipate and slow the escape of gases from a weapon muzzle and thereby reduces the normal muzzle report.
A hide selected and prepared for observation only, and therefore its Field of View and concealment are the most important selection criteria. Used by both military and law enforcement sniper teams, and in the case of the latter especially for the surveillance of remote airfields, clandestine drug labs, and borderlands.
A series of observation techniques the sniper team uses to pick out concealed or obscured targets.
The sniper's ability to identify a detected target and thus determine the target's priority. For instance, knowledge of enemy uniforms and formations enables the sniper to identify the leaders.
The declining order in which a sniper engages targets so that he shoots the most imporatant ones first Target priority will vary according to day and night and the situation. An enemy sniper is always a friendly sniper's first priority target.
Temporary wound cavity
The dramatic expansion of soft tissue that results from a bullet's passage, sometimes 10 inches or more in diameter. This phenomenon is impressive but only temporary and does not usually cause rapid incapacitation or death.
To compensate or "hold" high or low to hit targets beyond or short of a rifle's zero--the trajectory correlation to Kentucky windage.
That part of a bullet's flight when it strikes and passes through a medium until all energy is depleted, and deals extensively with wounds.
One of two techniques for engaging moving targets. The shooter swings with and ahead of the target, holding an appropriate Lead for the target's speed and range.
The arched path a bullet follows from a rifle's muzzle until it hits the ground. The steepness of this arch varies depending on the angle at which the shooter holds the rifle--and this, of course, will vary according to how far away his intended target is located.
One of two techniques for engaging moving targets. In this technique, the shooter picks a point ahead of the target, holds steadily on the point, then squeezes off a shot when the target arrives there.
Triangulation detection technique
A countersniper technique used to determine an enemy sniper's location. It involves pinpointing the enemy's direction of fire from two separated locations and plotting these on a map so as to identify a point through triangulation. Friendly snipers then scan this area for likely sniper positions until he is located and eliminated.
The undesirable practice of stretching your neck forward or back in order to see through your riflescope properly. Corrected either by lengthening the buttstock or changing the scope eye relief.
A means of measuring an optical device's low-light resolution and magnification, which is probably a more useful way for comparing scopes, binoculars, etc., for night use. Measured by multiplying the objective lens diameter by the device's power, then computing this figure's square root. For a 10x scope having a 40mm objective lens = 400, whose sqrt is 20.
The speed at which a bullet travels, in fps. The combination of velocity and bullet weight determine a round's kinetic energy.
Wall of green
The maximum distance you can see in a rural area, depending on thickness and breaks in the vegetation. This roughly jagged, semicircular "line" is where you focus mind and vision while walking in order to detect hostilities before the detect you.
"What is it" decoy
A curious object placed in a location covered by fire to lure inquisitive enemy soldiers into a sniper's sights. The object could be the guts of a damaged radio, a flag, etc. To be most effective, this ambush technique should draw the enemy into a spot he doesn't think could be hit by long-range fire and have no indicators of any hostile presence. Are best emplaced during darkness.
The lateral distance a bullet drifts in a crosswind, measured in inches at various distances. Some bullet shapes, such as round nose, are more susceptible to wind drift, but others, like boattail, are less affected.
The twisted, unstable departure of a bullet from its horizontal axis or trajectory, which results from perhaps nicking a branch or grazing a bone. These wild centrifugal forces debilitate accuracy, but the tumbling bullet inflicts buzzsawlike damage in flesh.