What Causes a Shotgun Cartridge to Misfire?

What Causes a Shotgun Cartridge to Misfire?

A shotgun cartridge may misfire due to issues such as a worn or broken firing pin, a weak mainspring, or dirt and debris restricting movement in the action. These faults prevent the primer from being struck firmly enough to ignite. Most misfires are caused by problems with the gun rather than the cartridge, so it’s important to have both the firearm and the ammunition inspected by your retailer or gunsmith to identify the true cause.

When a Cartridge Misfires

It can be disconcerting when you pull the trigger and hear a quiet click instead of the bang you’re expecting. Whether you’re shooting clays in competition or on a driven game day, a misfire can be a real disappointment.

But what actually causes a misfire? And what should you do when it happens?

Common Causes of a Misfire

More often than not, a misfire is the result of an issue with the shotgun rather than the cartridge itself. Some of the most frequent causes include:

• Worn or broken firing pin: The firing pin may be too worn to properly strike the primer, or may have broken entirely. 
• Weak mainspring (firing pin spring): A weakened spring might not deliver enough force to ignite the primer. 
• Dirt or debris: Fouling or foreign material in the firing pin channel or action can restrict movement, reducing impact energy. 
• Misalignment: Even a brand-new shotgun can experience teething problems, such as a slightly misaligned firing pin.

The good news is that these issues are usually simple and inexpensive to fix once identified.

How to Identify the Cause

Examining the primer on a misfired cartridge can often reveal whether the problem lies with the shotgun or the cartridge:

- Light primer strike: A shallow indentation in the primer can indicate that the firing pin has struck it with insufficient force to reliably ignite the primer. This may suggest an issue with the shotgun's firing mechanism, although further inspection is necessary to establish the cause.
- Off-centre strike: A dent noticeably off-centre suggests a worn, bent, or misaligned firing pin, which may cause intermittent misfires. 
- No strike at all: If there’s no indentation, the firing pin hasn’t contacted the primer, indicating a mechanical fault with the firing mechanism.
Comparing the primer indentation of a misfired cartridge to one that fired normally can help distinguish between a gun-related issue and a cartridge-related one.

What to Do if a Misfire Occurs

If a cartridge fails to fire:

1.   Keep the shotgun pointed in a safe direction and wait at least 30 seconds before opening the action, in case of a delayed ignition. 

2.   Do not attempt to refire the cartridge. 

3.   Set aside the misfired cartridge, along with any unused cartridges from the same batch, keeping the box with the batch code intact. 

4.   Return them to your retailer where they were purchased. 

5.   If possible, take your shotgun so the firing pins and action can be inspected by a qualified gunsmith.

A physical examination of both the gun and ammunition is the most reliable way to determine the cause of a misfire.

Why You Should Always Go Back to the Retailer

It’s rarely possible to diagnose a misfire from photographs alone. A hands-on inspection by your retailer or gunsmith allows the issue to be properly investigated and for a quicker, simpler resolution to be arranged. 

In the event that a cartridge fault is found, the retailer will manage the replacement process directly with us, the manufacturer. For that reason, the retailer should always be your first point of contact.

Reporting an Issue Directly

If you would like to report a cartridge issue directly, please email info@gamebore.com with:

• Description of the issue and supporting photographs 
• Cartridge name, load, shot size, and wad type 
• Batch code from the box label
• Retailer’s name and date of purchase

This information helps us log, investigate, and resolve the matter efficiently.

Our Commitment to Quality

Every Gamebore cartridge is manufactured under strict quality-control procedures to ensure consistent performance and reliability. 

We value all feedback from shooters, as it helps us maintain the high standards our customers expect from every cartridge we produce.