Letter D

The Definition of Drift

Arsenal Exchange - Firearms Classifieds - Industry Directory

Drift

The departure of a bullet or shot charge from the normal line of flight. This can be caused by wind or the unbalanced spinning of the bullet.


19 Other Firearms Definitions You Need To Know


Side-By-Side

A shotgun with two barrels which are situated next to each other. Somtimes also abreviated as SxS.

Jump

The amount of change in the bore axis, measured both vertically and horizontally, while the projectile moves from the chamber to the muzzle when it is fired.

Traditional Isosceles

In the Traditional Isosceles stance, Both arms are stretched almost equally forward with the gun centered forward. The knees are straight or only slightly flexed, and the entire body is upright and parallel to the target. This is an acceptable range stance provided recoil control is not an issue and you don't need to make rapid follow-up shots. However, if you are practicing for self-defense, you will probably want to use the Modern Isosceles stance stance instead.

Youth Rifle

A short, lightweight rifle. Some are small enough for a young child to easily handle, while others are large enough to perfectly suit teenagers, average-sized adult women, and small-statured adult males.

Chamber Throat

This is the area in the barrel that is directly forward of the chamber, which tapers to the bore diameter.

Parkerizing

A chemical phosphate process developed during the second world war to provide an economical, durable and non-reflective surface finish to military firearms.

Trigger Scale

A specialized type of hanging scale designed to test trigger pull weight.

Eye Dominance

Although we have two eyes for depth perception and for spare parts, there is a natural tendency for one eye (the master eye) to take precedence over the other, regardless of the relative visual acuity of each eye. It is a fortunate condition when the eye on the side of the shoulder where one is comfortable mounting a gun is also the dominant eye.
To test for eye dominance:

Pick out a small object several feet away. With both eyes open, center your right index finger vertically over the object. Close your right eye. If your finger appears to jump to the right, you are right eye dominant. Then open your right eye and close your left eye. If your finger remains in position in front of the object, you have confirmed your right eye dominance. Alternatively, if in the above test, upon closing your right eye your finger remains in position covering the object, you are left eye dominant. If you close your left eye instead and your finger appears to jump to the left you have confirmed your left eye dominance.
Eye dominance problems can be treated with
1. A severely-cast, crossover stock to bring the dominant eye in line with the gun's line of sight, 2. A patch over the dominant eye, or just a small piece of frosty Scotch tape on shooting glasses intercepting the dominant eye's line of sight, 3. Fully or partially closing the dominant eye, or 4. Learning to shoot from the dominant-eye shoulder.
While less convenient, methods that retain the use of both eyes better preserve the ability to perceive depth in three-dimensional space, a great benefit in wingshooting.

Timing

The proper adjustment of the various interrelated moving parts of a gun so that every operation works in proper sequence, such as that the two ejectors of a double gun kick out the spent cases at the same instant and with the same force.

Interrupted Thread

A screw with about half of its threading removed in longitudinal sections. Often used at the breech end of a takedown firearm's barrel. When the barrel's interrupted female threads are inserted into the receiver's complementary interrupted male threads, only a partial rotation is necessary for assembly rather than many full turns.

Snubby

Slang word for short barreled revolver.

Long Colt

Although a misused term (even within the firearms industry), Long Colt is a designation for an ammunition cartrige developed by Colt mainly used for revolvers. The actual designation is Colt instead of Long Colt. The term Long Colt was originally coined to avoid confusion between the .45 Colt and .45 ACP cartridges

Front Sight

The front sight is placed at the muzzle end of the barrel. It is often (but not always) in the form of a dot or a blade. To attain a proper sight picture and shoot with the greatest degree of accuracy, the shooter's eye should be focused sharply upon the front sight while shooting, allowing both the rear sight and the target to blur somewhat.

Passive Safety

Any safety, internal or external, which functions apart from the shooter's conscious control. Grip safeties are one example of a passive external safety.

Cylinder Drum

On a revolver, a spring activated device housed in the bottom of the frame beneath the cylinder that engages alignment notches in the cylinder. It stops the cylinder's rotation and holds it in place each time a chamber in the cylinder is in alignment with the barrel.

Headspace

The distance, or clearance, between the base of a chambered cartridge and the breech face (or bolt face) of a firearm. This is a critical dimension, particularly in high powered rifles. If there is too little headspace, the bolt will not close. If there is too much headspace the cartridge will not be properly supported in the chamber and the cartridge will expand upon firing and may rupture, blasting high-pressure gas into the action and possibly into the body of the shooter. Headspace should be .003" - .006" in a centerfire rifle. It can be checked with a set of "Go and No-Go" gauges specific to the calibre in question. (See below.) With a standard cartridge, the headspace is registered by the shoulder, with a belted cartridge, the headspace is registered by the forward edge of the belt.

Pellet (air gun)

Skirted projectiles used in pellet guns

Globe Sight

A front sight assembly, primarily for target rifles, consisting of a tube, housing interchangeable beads and blades. The tube guards against imperfect aiming due to sight pictures influenced by reflections.

Sights

The device that aids the eye in aiming the barrel of a firearm in the proper direction to hit a target.They can be a mechanical, optical, or electronic device. Iron sights or sometimes as open sights, consist of specially-shaped pieces of metal placed at each end of the barrel. The sight closest to the muzzle end of the gun is called the front sight, while the one farthest from the muzzle (and nearest to the shooter) is called the rear sight.