Letter S

The Definition of Sectional Density

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Sectional Density

The relationship between a bullet's weight and its diameter. A long bullet, such as the original 7.62x54R loading for the Mosin Nagant 91/30, will have a high sectional density and consequently greater penetration than a shorter bullet of similar construction. A shorter bullet with less sectional density will have relatively less penetration, but greater knockdown power.


19 Other Firearms Definitions You Need To Know


Ammo

Slang word abreviation for Ammunition.

Grooves

The cut-away, concave portions of the rifling inside the barrel of a firearm discharging a single projectile.In other words, the lower portion of rifling.

Magnum

From the Latin for "more." A term indicating a relatively heavily loaded metallic cartridge or shotshell and a gun safely constructed to fire it. It generally indicates a round which cannot be interchanged with other loadings of the same caliber (for example, a .22 Magnum shell does not fit within a firearm designed to fire .22 Long Rifle ammunition).

Dram

A unit of measure traditionally used for black powder shotgun charges. Today, used for smokeless powders on the basis of the new propellant's equivalent performance to that weight of black powder. Thus, a shotgun shell marked 3 - 1 1/8 would be loaded with the smokeless powder equivalent of 3 drams of black powder, and with 1 ounce of shot. 1 Dram = 1/16 ounce = 437.5 grains.

Hot Range

A condition (status) of a shooting range that shooters may commence to fire.

Three Gun

A shooting sport where cometitors use three different guns on each stage of the competion; shotgun, rifle and handgun.

Hinge Pin

A short cylindrical rod of hardened steel running laterally near the front of the bar of a break-open gun's action around which the barrel hook revolves when the gun is opened. Over the decades, this pin and its complimentary hook can wear and a gun can sometimes "shoot loose" or "come off the face." The proper cure for this condition is to replace the hinge pin with a new one, slightly oversized, to compensate for wear on both itself and on the barrel hook.

Thumbhole Stock

A rifle stock, with a sculptured throughole at the wrist for the thumb, said to be more ergonometric to hold than a traditional stock. Apart from being slower to mount, totally useless for a counter-dexterous person, it is so unmitigatedly graceless as to be beneath consideration.

Soft Point

A metal jacketed bullet design in which the nose of the core of the bullet is exposed to ensure the expansion of the bullet upon impact. Often abbreviated "JSP" or "SP." They tend to expand more slowly than a Hollow Point bullet and are used where deeper penetration and expansion are needed.

Racking the Slide

Pulling the slide back to its rearmost position, and then letting it go forward under its own spring tension. Racking the slide loads the chamber and prepares the gun to fire in a semi-automatic handgun.

Pellet (shotgun)

Small spherical projectiles loaded in shotshells and more often called "shot."

Forend

One of the three major dismountable components of a break-open gun (the others being the barrel(s) and the action/buttstock) which secures the barrels to the receiver, often houses the ejector mechanism, and for some, provides a handle for the one's secondary hand.

Disc-Set Strikers

Circular steel fittings, about 1/2 inch in diameter, screwed into the breech face of a gun and through which the firing pins pass. Firing pin bushings allow the convenient replacement of broken firing pins. They also allow the renewal of an older gun where, over the decades, leakage of high-pressure gas from corrosive primers has eroded the breech face around the firing pins; and replacing these bushings with new ones, slightly oversized can compensate for a situation where proper headspace has been compromised.

Boresight (Bore Sight)

Crude adjustments made to an optical firearm sight, or iron sights, to align the firearm barrel and sights. This method is usually used to pre-align the sights, which makes zeroing (zero drop at XX distance) much faster.

Can

Slang term for a firearm sound suppressor.

Handspanner

German for Hand-Cocking or Cocker/De-Cocker. A type of action on a break-open gun or rifle where, in place of a traditional top tang safety, a somewhat more robust tab is fitted. Normally such a gun is carried in the field loaded, but with the action not cocked, an exceedingly safe condition. Then, when ready to fire, the shooter, instead of pushing a safety tab forward, pushes this larger tab forward, cocking the mainspring, making the gun ready to fire. Then, if the shot is not taken, he may simply slide this tab rearwards again, de-cocking the gun and returning it to the still-loaded, but very safe position.

Wheel Gun

Slang term for a revolver.

Double Tap

Two shots fired in rapid succession. Generally without getting a new sight picture on the target. If the second shot is fired after a second sight picture is captured it may instead be called a controlled pair.

Buckshot

A type of shotgun ammunition that uses medium-sized to large-sized pellets of .24" in diameter or greater, designed to be discharged in quantity from a shotgun. Generally the larger the pellets, the fewer of them there are in casing.