Gun Machining Basics

A gun is a complex tool. Bat machining also originated from this. Gunsmithing consists of many moving parts and a variety of materials, each carefully selected for specific properties. Tactical Machining LLC is dedicated to manufacturing the highest quality firearms parts. Chisel Machining and ecco Machining are both good choices for manufacturers.

The goal is to create a reliable and durable gun that fires whenever the trigger is pulled and the safety is off.

Over the centuries, as our engineering knowledge has increased and material science (especially metallurgy) has advanced, the parts of a gun have evolved.

In this article, we will explore the materials used to make guns, including the metals used in gun manufacturing, the main components of a gun, and the gun fasteners that hold them together.

1.What is gunmetal?

Modern gun machining may include many different materials: wood, plastic, carbon fiber, and even ceramic. But metal remains the main material, especially for gun frames and barrels, chambers and barrels, and fire control components.

The term “gunmetal” is often used to describe the metals used in gun manufacturing. However, modern guns are made of many different metals, each with specific hardness, machinability, durability, and cost characteristics.

The original gunmetal was a bronze, an alloy consisting of copper, tin, and zinc. It is also known as red brass. This copper alloy is still used in applications where its corrosion resistance is needed, although it is rarely used in guns. The vast majority of firearms are made primarily of various types of carbon steel, but also include stainless steel, aluminum, and other alloys.

It’s safe to say that most of the critical components of modern firearms you encounter are made of steel. But the name “steel” doesn’t refer to a single metal; it’s a broad range of iron alloys that contain precisely calibrated amounts of carbon and other metallic and nonmetallic elements, including nickel, chromium, cobalt, molybdenum, and tungsten.

1) Carbon Steel

The amount of carbon in a steel affects its hardening characteristics. Broadly speaking, there are three types of carbon steel: low carbon (also called soft carbon), medium carbon, and high carbon.

These steels have carbon contents between 0.3% and 0.75%. As the carbon content increases, the hardness and strength of the steel also increase.

However, increased hardness reduces the steel’s ductility, machinability, and weldability. High carbon steels are also more brittle.

This makes high carbon steel unsuitable for many applications in cost-effective firearm manufacturing, which tends to use soft and medium carbon steels to strike a balance between hardness and machinability.

① Commonly used carbon steels in gun machining include:

1.4140 steel: Also known as ordnance steel, it contains 0.4% carbon and small amounts of chromium, manganese, and other metals. 4140 steel is a hard and durable steel used to make many gun parts such as barrels, bolts, and receivers.

2.4150 steel: Similar to 4140 steel, but with a higher carbon content. It is harder than 4140 steel, but more difficult and expensive to process, so it is more commonly used in military firearms.

3.1020 or 1520 carbon steel: is a low carbon steel. It is softer and is often used for gun parts that are under less pressure, such as trigger guards and sights.

While these are the most commonly used carbon steels, you will also encounter other varieties of guns, including the proprietary Carpenter 158, which is used to make bolts for some guns that meet military specifications.

2) Stainless steel

In addition to carbon steel, gun manufacturers may also use stainless steel. Stainless steel is a rust-proof and heat-resistant iron alloy that contains high amounts of chromium and other elements, such as nickel and molybdenum.

Like carbon steel, there are many varieties of stainless steel, with varying properties depending on the combination of elements added to the iron.

3) Aluminum Alloys

While most gun parts that are subject to significant forces are made from steel, some parts may be made from anodized aluminum.

The most widely used aluminum alloy is 6061 aluminum, also known as aircraft aluminum, which contains magnesium and silicon. 6061 aluminum is often used for secondary chambers and suppressors.

The stronger 7075 aluminum alloy is used in some receivers—such as the AR-15. However, it is used more in military applications than in consumer guns.

4) Titanium

Finally, some manufacturers use titanium, which is stronger than aluminum but lighter than carbon steel. Titanium is not as strong as carbon steel, and titanium parts are more expensive to manufacture.

It is not typically used for parts that are subject to significant forces, such as barrels or bolts. Some guns are made primarily of titanium, but they are much more expensive than steel guns, and in most cases, the gun contains only a few small titanium parts, such as frame components, fasteners, and revolver shells.

2.Parts of a Gun

We’ve looked at the materials that guns are made of, but how do they form a usable gun? Guns come in many types, from large artillery pieces to pocket pistols, with varying designs and uses.

Our non-exhaustive analysis covers the major parts of consumer-grade guns, their functions, and the materials they are made of.

1) Receiver/Frame

The receiver (frame in a pistol) is the part of a gun that houses and supports the other parts. It contains the trigger mechanism and “houses” the barrel, stock, sights, etc. The receiver is typically made of steel or aluminum and is manufactured by stamping, machining, or forging.

2) Action

In modern repeating firearms, the action is the mechanism that loads the bullet from the magazine, fires it, extracts the shell from the chamber, and ejects it from the gun.

The action can be manual, in which case the user cycles the action after firing, or automatic. Automatic bolt actions use the energy created when firing to complete the cycle.

There are many different bolt action designs; they are often complex mechanisms with many moving parts, levers, springs, and fasteners. They are often made of carbon steel, stainless steel, and spring steel.

3) Fire Control Group

The fire control group or trigger group consists of components such as the hammer or firing pin, the safety, and the trigger sear. The trigger sear blocks the hammer or bolt, which blocks the firing pin, until the trigger is pulled.

In short, they are the components that make the gun fire when the trigger is pulled. Fire control groups are usually made of steel, but may also contain aluminum or titanium components.

4) Chamber

The chamber holds the bullet before firing. Revolvers have a multi-chamber chamber into which the user inserts the bullet, while pistols and rifles have only one chamber, which is located at the rear of the barrel. The chamber is subject to a lot of force during firing, so it is usually made of strong carbon steel.

5) Barrel

The barrel is the tubular component that the projectile passes through when fired. The chamber is located at the rear of the barrel, and after the projectile enters the chamber through the breech, it passes through the chamber and is fired out of the muzzle at the front of the firearm.

When firing, the barrel is subjected to extreme forces due to the rapid expansion of high-pressure gases and the passage of the projectile. The barrel must be able to withstand these forces for hundreds of shots.

It is usually made of carbon steel or stainless steel, but some sports and competition guns use thinner metal barrels and outer carbon fiber sleeves.

6) Magazine

The magazine of a firearm is used to store ammunition until the ammunition is inserted into the chamber through the breech. Magazines can be either integrated or detachable.

Detachable magazines are often called clips, although the definition of clips may be narrower, that is, not including magazines with integrated feeding mechanisms. The correct terminology is controversial.

Detachable magazines are often made of cheap stamped metal because they are not subjected to the same extreme forces as other parts of the firearm.

3.Firearm Fasteners

We have already covered the materials and major firearm components used by gun manufacturers, but another component group is just as important: firearm fasteners.

Firearm fasteners hold other components together. Without them, a gun is just a pile of parts.

1) Pins

Pins are short cylindrical metal or plastic fasteners used to align and secure components.

There are several different types of pins used in gun manufacturing, including:

1. Dowel pins: Cylindrical rods used to align or connect components.
2. Spring and roll pins: Tubular pins with grooves that create a spring force when inserted into a smaller diameter hole.
3. Grooved pins: Solid pins with grooves or channels that close when the pin is pressed into the hole, creating a force that holds the pin in place.
4. Tapered pins: Pins that taper in length. Tapered pins are held in place by friction.
5. Dowel pins: Pins with a retaining spring ball bearing on one end. Dowel pins are easy to insert and remove while providing adequate holding force for many applications.

2) Push-on fasteners and retaining rings

This is a diverse category of fasteners used to secure parts to shafts, pins, and studs and create anchor points.

1.Palnut Push-Ons: One-piece engineered fasteners that work with round, threaded, or custom studs.

2.Retaining Rings: Retaining rings that secure parts to slotted shafts or pins.

3.Rectangular Retaining Rings: Retaining rings with a rectangular cross-section, typically used to secure parts to shafts or in holes.

4.E-Clips: A wide-shouldered radial clamp with a fork that inserts into machined grooves on tubes, pins, and shafts.

3) Washers and Spacers

Washers and spacers play a variety of roles in gunsmithing, such as acting as shims, distributing fastener loads, preload other components, and more.

1.Shim Rings: Also known as tolerance rings, shim rings are installed on bearings to prevent axial movement and create a buffer between components.

2.Variable Spacers: Used to increase or decrease the effective length of a shaft or bolt.

3.Belleville Washers: Spring washers that preload joints and bearings.

4. Lock washers: Toothed bearing lock washers and split lock washers help prevent screws and bolts from loosening.

4) Other firearm fasteners, parts, and tools

In addition to the fasteners we have already discussed, gun manufacturers and gunsmiths use many other small parts to assemble guns, create anchor points, and assist in construction.

1. Flange bearings are oil-impregnated bushings that support loads while allowing the shaft to rotate freely within the bearing.
2. Lock nuts are designed to resist loosening under vibration and other forces. They consist of metal or plastic that deforms when the nut is installed, creating friction that holds the nut in place more effectively than a nut that rotates freely.
3. O-rings are gaskets that form a gas or liquid seal at the interface between mating parts.