Bullet Plug Wire Harness: Connect a bullet plug to a wiring harness

There are hundreds of varieties of electrical connectors. The functioning of electrical devices and electronic equipment depends on these connectors. Some connectors are designed to permanently connect multiple wires, while others form a temporary connection between cables. The bullet plugs fall in the second category and are the most common in the wiring harness. We will study the bullet plug wire harness.

What are bullet plugs?

The primary function of the bullet plugs is to connect two wires. For this, you need both male and female bullet connectors, with the male having a bullet shape while the female has a socket shape. The bullet-shaped terminal in the male connector connects to the hollow socket of the female of the same size. Mating male and female bullet connectors give you a very tight and secure connection and can connect and disconnect easily.

Bullet plugs, also called bullet terminals or barrel connectors, comprise properly tempered pure electrolytic copper that forms a fused connection on crimping. The bullet connector gives maximum strength and conductivity with this fused connection. Also, you will find that the terminals come with electro-bright tin plating to prevent corrosion.

The size of the bullet plugs may vary from 0.156 inches to 0.180 inches. Further, they come in various gauge sizes ranging from 16-14 gauge up to 22-18 gauge.

You can use bullet connectors in various applications, including home entertainment systems, automotive products, speaker wires, lighting, and climate control systems.

Standard power connectors XT60 and bullet

Standard power connectors XT60 and bullet

Advantages of Bullet Connectors

Bullet connectors do not form a permanent connection but rather a temporary connection. You can choose to separate the two wires or reconnect.

These small connectors are very helpful if you want to connect wires in tight spaces.

These connectors form a very reliable and robust connection. There are no chances of connectors disconnecting from wires on their own if you have mated the male and female connectors tightly and correctly.

Bullet plug types:

Bullet plugs come in different insulation coverings, including heat shrink, nylon, and vinyl.

Heat-shrink bullet plugs: 

These plugs have adhesive lining and come with color coding according to industry standards. The heat shrink used in these connectors is transparent and gauge printed for visual inspection. Heat-shrink insulation completely seals the terminal and is thus the most durable compared to vinyl and nylon. As a result of complete sealing, the bullet connector with heat-shrink insulation gets protection from water damage and corrosion. These connectors have a rating of 600 volts maximum, building wire 1000 volts at 105 degrees Celsius.

Nylon-insulated bullet plugs:

These have a brazed seam that will not separate under pressure or stress. Clear nylon prevents deformation due to stress and heat. Nylon-insulted bullet connectors come in either standard form or with a brass sleeve. These connectors come with a 600 volts maximum rating at 221-degree Fahrenheit.

Vinyl insulated bullet plugs:

You can find these connectors wire-wise, ranging from gauge 22 to gauge 14. These connectors have PVC or polyvinyl chloride insulation around the tin-plated copper terminal on the inner side. Due to PVC coating, these connectors come at an affordable price. These are suitable for use at 600 volts highest and have a temperature rating of 105 degrees Celsius.

A set of blue bullet plugs

A set of blue bullet plugs

How to Assemble a Bullet Plug Wire Harness.

Both versions have a hollow interior end with conductive material at the inner wall. Mostly, this conductive material is copper.

You must first strip the insulation from the wire ends to attach the bullet connectors onto the wire. Once stripped, slide in the connector over the wire’s end. Once you align the male and female connectors over the wires’ exposed ends, you can crimp the connection. 

Then, how to crimp wire bullet terminals?

Crimping helps to make the connection tighter and more secure. However, you should have the right skill and correct knowledge of crimping bullet terminals; otherwise, it may lead to poor connection and disconnection.

  1. First, get the correct crimping tool.
  2. Now, use the crimping tool with a cutter to cut the wires.
  3. Pass the insulation sleeve.
  4. According to the thickness of the wire, prepare a wire stripper and select the teeth. 
  5. Now, strip the wire, and the wire length is about 1mm longer than the crimped portion.
  6. Now pinch the bullet terminal and insert the wire into the crimping part. 
  7. After wire insertion, hold the crimping tool firmly and crimp the core wire.
  8. Check the wire and ensure the terminal insulation part fits appropriately in the specific portion.


Bullet connectors are highly reliable connectors for use in small spaces. However, it is essential to properly plug the male connector into the female socket to take advantage of these connectors. If you need a bullet plug wiring harness, Cloom can help you get some very high-quality options.

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I am a responsible, intelligent and experienced business professional with an extensive background in the electronics industry.

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