Caliber
The diameter of the bullet or bore, often shown as numbers like 9mm, .22 LR, .380 ACP, or .45 ACP.

Magazine
The part that holds ammunition and feeds it into the firearm. A magazine is not the same thing as a clip.

Chamber
The part of the firearm where a round sits before it is fired.

Slide
The moving top part of many pistols. It cycles back and forward when the firearm operates.

Frame
The lower part of a pistol that holds the grip, trigger, and internal parts.

Barrel
The tube the bullet travels through when fired.

Trigger
The part pressed by the shooter to fire the firearm.

Sights
The aiming system on a firearm. These may be iron sights, night sights, fiber optic sights, or optics.

Round
One complete cartridge of ammunition.

Cartridge
A complete unit of ammunition made up of the case, primer, powder, and bullet.

Bullet
The projectile that leaves the barrel. The whole thing is not called a bullet — it is a cartridge or round.

Primer
The small ignition component at the back of a cartridge.

Case / Casing
The metal shell that holds the primer, powder, and bullet.

Grain
A unit of weight used to measure bullet weight. Grain does not automatically mean “power.”

FMJ
Full Metal Jacket. A common range ammo type often used for practice.

JHP
Jacketed Hollow Point. A defensive ammo type designed to expand.

+P Ammo
Higher-pressure ammunition. Only use it if your firearm is rated for it.

Steel-Cased Ammo
Ammunition with a steel case instead of brass. It is often cheaper but may run dirtier in some firearms.

Brass-Cased Ammo
Ammunition with a brass case. It is common, reliable, and widely used for range and defensive ammunition.

Muzzle Discipline
Keeping the muzzle pointed in a safe direction at all times.

Trigger Discipline
Keeping your finger off the trigger until you are ready to shoot.

Backstop
The safe area behind the target that stops bullets.

Cease Fire
A command to stop shooting immediately.

Safe Direction
A direction where an unintentional discharge would be least likely to cause injury or damage.

Loaded Firearm
A firearm with ammunition in it. Treat every firearm as loaded unless you have personally verified otherwise.

Clear / Unloaded
A firearm with the magazine removed, chamber checked, and no ammunition present in the firearm.

Lane
Your assigned shooting area at the range.

Target Distance
How far the target is from the shooter.

Point of Aim
Where you are aiming.

Point of Impact
Where the bullet actually hits.

Group / Grouping
The pattern of shots on the target.

Malfunction
When the firearm does not operate correctly. This can be caused by ammo, grip, maintenance, or mechanical issues.

Failure to Feed
When a round does not properly enter the chamber.

Failure to Eject
When the spent casing does not fully leave the firearm.

Stovepipe
A type of malfunction where the spent casing gets stuck sticking upward or sideways from the ejection port.

Holster
A carrier designed to safely hold a firearm.

Retention
How securely a holster holds the firearm.

Concealment
How well your firearm and gear stay hidden during daily carry.

Red Dot Sight
An optic that shows an aiming dot. Many beginner issues with red dots come from presentation, not the optic.

Weapon Light
A light mounted to a firearm. It can help you see, but poor use can also give away your position.

IFAK
Individual First Aid Kit. A compact emergency medical kit.

Range Bag
A bag used to carry range gear like eye protection, ear protection, ammo, targets, tools, and cleaning supplies.

Eye Protection
Safety glasses used to protect your eyes from debris, brass, and other range hazards.

Ear Protection
Hearing protection used at the range. Indoor ranges are especially loud, so doubling up with earplugs and earmuffs is often a smart choice.

Riding the Slide
Holding or slowing the slide as it moves forward. This can cause feeding issues on many pistols.

Limp Wristing
Not giving the firearm enough support during recoil. This can sometimes cause cycling problems.

Lighthousing
Leaving a weapon light on too long or using it carelessly, which can reveal your position.

Over-Gripping
Squeezing the gun so hard that it creates tension and affects accuracy.

Anticipating Recoil
Moving the firearm before the shot breaks because you expect the recoil.

Poor Presentation
Bringing the firearm up inconsistently. This is a common reason beginners struggle to find their red dot.