Firearm Terminology: A Gunsmith's Guide to Understanding Your Weapon

From the Bench: Essential knowledge for every firearm owner

By Hootey Cline, Blue Coat Arms Company

Originally published June 12, 2019 | Updated July 1, 2025

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Every time a customer walks into my shop and starts mixing up clips with magazines or asking about "that thingy that makes it shoot," I'm reminded why firearm terminology matters. Whether you're discussing a repair with your gunsmith, talking to other enthusiasts, or simply want to understand what you own, proper terminology is the foundation of firearm knowledge.

The reality: Many people hear and read about firearms without understanding what the terms actually mean. This creates confusion, miscommunication, and sometimes dangerous situations.

Let's fix that.

Why Terminology Matters

When someone calls asking about "clips" for their AR-15, I immediately know they're new to firearms. That's not a judgment – we all started somewhere. But using correct terminology helps you:

• Communicate effectively with gunsmiths and dealers

• Understand what you're buying or discussing

• Sound knowledgeable in firearms conversations

• Stay safe by understanding your equipment

Shotguns: The Versatile Platform

Barrel Considerations

Shotgun barrels are all about purpose. The key questions are:

• What are you hunting?

• What's your intended use?

Length affects:

• Velocity: Longer barrels generally increase projectile speed

• Accuracy: More barrel length typically improves precision

• Maneuverability: Shorter barrels are easier to handle in tight spaces

Shot Dispersion and Back-Boring

Shotguns naturally disperse smaller shot better than larger pellets. To optimize patterns with larger shot, consider back-boring – oversizing the bore to accommodate larger pellets while reducing felt recoil.

Forcing Cone: The Critical Transition

The forcing cone is the tapered area in front of the chamber that funnels shot into the barrel. This component has evolved significantly:

Historical context: In the "good old days," shotgun wads were made of felt, requiring very short forcing cones.

Modern reality: Today's plastic wads require longer forcing cones for optimal performance. Short cones:

• Deform shot pellets

• Increase felt recoil

• Reduce pattern consistency

Important note: Chrome-lined barrels often cannot have their forcing cones modified due to the coating.

Choke: Pattern Control

Choke serves the same function as the forcing cone but at the muzzle end. Different choke constrictions control shot spread:

• Cylinder: No constriction (widest pattern)

• Improved Cylinder: Slight constriction

• Modified: Medium constriction

• Full: Maximum constriction (tightest pattern)

Sights and Pointing

Critical distinction: You don't "aim" a shotgun – you point it.

Middle bead: Not for aiming, but to prevent canting (tilting) side-to-side. Particularly useful for trap shooters due to the natural slope of the chest cavity.

Pitch Angle: The Fit Factor

Hold an empty shotgun perpendicular to a wall, and you'll notice the barrel points slightly downward. This downward pitch is critical for proper fit, especially for women, affecting both accuracy and recoil control.

Point of Impact vs. Point of Aim

Point of Impact is where your shot actually hits – not necessarily where you're pointing. Factors affecting this include:

• Un-square rib installation

• Un-square choke installation

• Barrel regulation issues

Fun Fact: The Tampon Connection

Tampons were, supposedly, invented by a British gunsmith for double-barrel shotguns. They were U-shaped cloths dipped in oil and placed in barrels to prevent rust, complete with a string for removal. The official patent was filed by an American physician, Dr. Earle Haas, in 1931.

Rifles: Precision Instruments

The Barrel: Your Most Critical Component

The barrel is the most critical part of any rifle. While factory barrels are generally decent, they're still mass-produced to meet cost targets, not achieve maximum precision.

Bedding and Free-Floating

Bedding: How the action sits in the stock Free-floating: Ensuring the barrel doesn't touch the stock except at the action

Both affect accuracy significantly.

Crown: The Final Touch

The crown is the muzzle end of the barrel. Even minor damage here can dramatically affect accuracy.

Head-space: Critical Safety

Head-space is the distance between the bolt face and the chamber. Incorrect headspace can be:

• Dangerous (too little space)

• Inaccurate (too much space)

Stress Relief Through Cryogenics

Cryogenic treatment at -475°F relieves manufacturing stress in barrels, potentially improving accuracy and barrel life.

Trigger Jobs: The Interface

A trigger job reduces the pressure needed to fire while maintaining safety. A crisp, consistent trigger is essential for precision shooting.

Scopes and Mounting

Scopes and sights are invaluable for realizing a rifle's true potential, but they must be mounted properly. Poor mounting negates even the best optics.

Blueprinting: Precision Assembly

Blueprinting ensures everything is perfectly aligned with the firing pin hole. Most factory barrels are considered "Class 4" fit, while "Class 5" represents the highest precision standard.

Lock Time and Accuracy

Lock time is the duration from sear release to bullet exit. Shorter lock times generally improve accuracy by reducing movement during firing.

Important note: Lever guns don't work reliably at all angles and speeds. Understanding your firearm's limitations is crucial for safe operation.

Handguns: Personal Defense and Sport

Platform Types

Semi-automatics and revolvers are the most common handgun types, each with distinct advantages and terminology.

Co-Witness Sights

Co-witness sights combine iron sights with red dots or optics, sighted together so either can be used. While useful for competition, they add too much bulk for concealed carry.

Barrel Lapping

Barrel lapping creates concentricity throughout the barrel bore, improving accuracy potential.

Compensators vs. Plain Models

Compensators redirect muzzle gases to reduce felt recoil and muzzle rise. Consider whether your intended use justifies the added complexity.

Chamber and Throat Relationships

The relationship between chamber and throat differs significantly between semi-autos and revolvers, affecting how bullets enter the rifling.

Lands and Grooves

Lands are the raised portions of rifling; grooves are the valleys between them. Most military rifles have 4-6 lands and grooves.

Slide-Frame Fitment

Slide-frame fitment affects accuracy:

• Too loose: Poor accuracy

• Too tight: Reliability issues

Guide rods help by forcing consistent positioning during the battery phase while protecting the frame from recoil shock.

Springs: The Unsung Heroes

Springs are critical for semi-auto function:

• Variable rate springs: Change tension as compressed (preferred)

• Standard rate springs: Consistent tension throughout compression

Grips: Form Meets Function

While grips offer personalization opportunities, they must still secure the firearm during recoil. Style shouldn't compromise function.

Sight Types

• Fixed sights: Non-adjustable

• Adjustable sights: Allow point-of-impact changes

Ejection Port Modifications

The ejection port is where spent cases exit. Common modifications include:

• Lowering: Easier case ejection

• Relieving: Notch cut to minimize snagging

Most malfunctions occur when cases hit the breech plate or catch on the ejector.

Port and Polish Work

Feed ramp polishing ensures smooth cartridge feeding.

Throating and Polish

Removing sharp edges from the feed ramp top prevents cartridge damage during feeding.

Barrel Hood

The barrel hood is the area fitted to the slide, affecting lockup and accuracy.

Disconnector: Critical Safety

The disconnector prevents firing while the action is cycling – a crucial safety feature that prevents runaway full-auto fire.

Magazine Wells

Magazine well enlargement allows easier magazine insertion and removal – particularly valuable in competition or defensive situations.

Slide Modifications

Fluting adds ribs to the slide for increased rigidity and improved accuracy.

Beaver-tail: Comfort and Protection

The beaver-tail spreads recoil over a larger hand area while protecting against "hammer bite."

Rear Serrations

Rear serrations reduce glare and improve grip when racking the slide.

Slide Stop

The slide stop locks the slide open on an empty magazine.

Magazine Catch

The magazine catch secures and releases the magazine.

Firing Pin Variations

Firing pins vary in diameter and material depending on the cartridge and ignition system.

Safety Systems

Various safety types exist for different applications, but remember: YOU are the most important safety. Mechanical safeties are backups to proper handling.

Revolver-Specific Terms

Cylinder Components

• Cylinder latch: Locks the cylinder in place

• Cylinder throat: Area in front of each chamber

• Cylinder/barrel gap: Critical spacing between cylinder and barrel

Speed Loaders

Speed loaders hold the exact number of rounds for your cylinder, allowing simultaneous loading of all chambers.

Crane Assembly

The crane assembly is often the weakest part of a revolver, allowing the cylinder to swing out for loading.

Crane Locking Detent

The detent is the recessed area where the crane assembly locks. Locking-ball detents are considered superior to other designs.

Modern Terminology Updates for 2025

Smart Gun Technology

Biometric locks and RFID systems are emerging in modern firearms, requiring new terminology around electronic safety systems.

Modular Systems

Modern firearms increasingly use modular designs allowing component swapping without gunsmith intervention.

Advanced Coatings

Cerakote, DLC (Diamond-Like Carbon), and other advanced finishes require specific terminology for proper communication.

The Professional Difference

At Blue Coat Arms Company, we're one of the gunsmithing shops in central Illinois with formal training from an accredited program (Sonoran Desert Institute). This education, combined with decades of hands-on experience, allows us to:

• Communicate effectively using proper terminology

• Educate customers about their firearms

• Perform precise work because we understand the technical aspects

• Troubleshoot problems other shops might miss

We're also actively involved in Research and Development projects, keeping us current with evolving terminology and technology.

Common Mistakes to Avoid

Clips vs. Magazines

Magazine: Holds cartridges and feeds them into the chamber

Clip: Loads cartridges into a magazine (like a stripper clip)

Using "clip" when you mean "magazine" immediately signals unfamiliarity with firearms.

Bullets vs. Cartridges

Bullet: The projectile only

Cartridge: The complete round (bullet, case, powder, primer)

Automatic vs. Semi-Automatic

Automatic: Continues firing while trigger is held

Semi-automatic: One shot per trigger pull

Why Education Matters

Understanding firearm terminology isn't about showing off – it's about:

• Safety: Knowing your equipment prevents accidents

• Communication: Clear terminology prevents misunderstandings

• Maintenance: Proper care requires understanding components

• Legal compliance: Laws often use specific terminology

The bottom line: Education and proper terminology are the foundation of responsible firearm ownership.

From the Gunsmith's Perspective

After decades of working on firearms from muskets to modern sporting rifles, I can tell you that terminology matters more than most people realize. When a customer can accurately describe their problem using correct terms, diagnosis becomes faster and more accurate.

Remember: Lever guns don't work at all angles and speeds. Education and knowing what you're using and how to use it properly are the keys to success with any firearm.

No matter your era, we got your six – and that includes helping you understand the terminology that makes you a more knowledgeable, safer firearm owner.

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Questions about firearm terminology or need work done on your firearms? Contact Blue Coat Arms Company at 217-416-5962 or BlueCoatArms@gmail.com. We speak your language – properly.