Laminated Case - A case which shows spots where the metal has separated in layers due to scaly inclusions.

Lands - In a rifled barrel, the raised spiral ribs left between the grooves in the bore.  This is the part of the barrel that actually engraves the bullet, imparts the spin to the bullet, and ultimately stabilizes the bullet.

Lead - The modified point of aim in front of a moving target needed to ensure a hit. This depends on the range to, and the speed of, the target.

Leading - Traces of lead deposited in the bore by cast bullets, particularly if not adequately lubricated. A build-up of such deposits results in poor accuracy. See Fouling.

Leaky Primer - The escape of gas around the primer pocket, indicated by gas leak around the primer cup.

Length Of Pull - The distance from the centre of the trigger to the centre of the buttplate or recoil pad.

Length Of Stock - The greatest dimension of the stock material.

Lever Action - Usually a repeating type of action with a reciprocating breechblock powered by a finger lever.

Light Blow - A weak firing pin blow, insufficient to discharge the primer properly.

Line Of Bore - Imaginary straight line following the axis of the bore. Of theoretical value only, as a bullet begins to drop below the line of bore from the moment it exits the muzzle. Also known as ‘line of departure’. See Line of sight, Trajectory. ( Click here for picture. )

Line Of Sight - Straight line from the shooter’s eye, along the sights to the point of aim. The sights on any rifle are mounted in such a way that the line of bore converges with the line of sight between about 10 and 30 meters from the muzzle, hence the bullet ‘rises’ to cross the line of sight at this point. However, gravity acts on the bullet, giving it a curved flight path which falls to cross the line of sight again at a preselected distance (the ‘zero range’). See Line of bore, Trajectory. ( Click here for picture. )

Load - Verb (1) to charge a firearm in preparation for shooting; (2) to assemble a cartridge by priming it, filling it with powder and inserting a bullet. See handload/reload. Noun: describes a given combination of bullet weight, bullet type, primer, powder charge and case.

Loading Density - The ratio of the volume of the powder charge to the volume of the case.  The higher the better in terms of accuracy.

Loophole - Firing port. A hole cut to conceal the sniper but allow him to engage targets in his sector.

Low Primer - A primer which is inserted too deep into its pocket.  This may result in a hangfire or a misfire.

Lock - A general term referring to the total firing mechanism in a firearm.

Lock Time - The period of time between sear release (when the trigger is pulled) and the fall of the firing pin on the primer (determined by lockwork design).  No shooter can hold a rifle absolutely steady, and the longer the lock time, the more opportunity there is to disturb the aim during the firing pin’s travel, resulting in accuracy discrepancies.

Long Gun - A term used to describe shotguns and rifles.

Lube Dent - A dent in a cartridge case caused by using too much lubricant when resizing.

Lube Grooves - Circumferential grooves on a cast lead bullet, containing grease to reduce barrel friction and therefore barrel leading. See Leading, Fouling.

Lube Pad - A pad, impregnated with lubricant, on which cases are rolled before resizing.

Lubricant - Case sizing lubricant is used to reduce friction between the case and the die during the resizing operation in reloading - only applicable to full-length sizing.

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