SAAMI - Small Arms and Ammunition Manufacturers Institute. The organization which establishes firearms and ammunition standards in the United States.


Sabot - From French for "shoe". In modern small arms usage, a light-weight carrier or holder in which a sub-caliber projectile is centered to permit firing the bullet in a larger caliber barrel. Sabots are usually the discarding type; they fall away from the bullet soon after exiting the gun barrel. Pronounced "SAY-bo."


Seating Depth - In a loaded cartridge, the depth to which the base of the bullet is seated below the case mouth.


Sectional Density - A bullet's weight in pounds divided by the square of its diameter in inches.


Shank - The cylindrical section of a bullet below the ogive. The shank usually defines the bearing surface.


Shell Holder - The part of a reloading press that holds the head of the cartridge case on the ram.


Shock - See hydrostatic shock.


Shock Wave - The compression wave formed whenever the speed of a projectile relative to air or other medium exceeds that at which the medium can transmit sound.


Shot - The lead alloy spheres, sometimes copper or nickel-plated, that are used for the projectiles in shotguns. Chilled shot is hardened. Drop shot is very soft.


Shoulder - The sloping or rounded part of a bottleneck cartridge case between the neck and the body.


Sighting in - Firing a rifle or pistol to determine its point of impact at a specified range and adjusting the sights so the point of impact has the desired location with regard to the point of aim.


Single-base Powder - Nitrocellulose powder made without the addition of any other highly nitrated chemical such as nitroglycerine. See double base powder.


Single-stage Reloading Press - A reloading press that hold only one reloading die at a time. For example, a sizer die in inserted and all cases are sized individually, then the sizer is removed and replaced with another die and a different operation is preformed on all cases. Contrast to progressive reloading press.


Sizing - Also resizing. Reducing a fired cartridge case to dimensions that allow easy chambering in a firearm of the appropriate caliber. May be full length, partial, or neck sizing. Bullets are also sized or reduced in diameter by forcing through a die.


Slug - A large, single projectile, often bearing external pre-cut rifling, intended for adapting shotguns to the hunting of larger game such as deer. Also a slang term for bullet. As a verb, "to slug" means forcing a soft lead slug through the bore of a gun and measuring it to determine barrel dimensions.


Smokeless Powder - A nitrocellulose-based propellant. Leaves a non-corrosive residue, but normally produce small amounts of smoke. Named because smoke production is very small compared to the older black powder.


Soft point (SP) - Bullet design feature in which a portion of the lead alloy core is exposed at the tip of a jacketed bullet.


Spent - In shooting, a cartridge or component thereof that has been fired.


Spherical Powder - A registered trademark of Hodgdon Powder Company use to describe round or semi-round grained powders. See ball powder.


Spin - The rapid rotation of the projectile caused by the spiral rifling of the bore. At the muzzle of a high-velocity rifle, spin can be in excess of 300,000 revolutions per minute.


Spire Point - A conical pointed bullet. The line from the shank to the point is nearly straight. See the .308" 110 grain bullet in the 30 caliber rifle section for an example.


Spitzer - Bullet design feature from German for "point". A bullet with a pointed nose. The line from the shank to the tip is arched. Compare to spire point above.


Stabilize - To spin a projectile around its long axis rapidly enough to keep it point-on in flight.


Swage - To form by forcing into or through a die. Rhymes with "age".