Strike Industries AR-THJ Trigger Hammer Jig - Black Steel for AR Platform Rifles

The Strike Industries AR-THJ Trigger Hammer Jig is a specialized gunsmithing tool designed for AR platform rifle builders and gunsmiths who need to diagnose, adjust, and tune trigger assemblies outside the rifle. Unlike trial-and-error tuning with the parts installed in your lower receiver, this jig lets you observe exactly how your sear, hammer, and disconnector engage while under live spring tension—so you can dial in function with precision and confidence before final assembly.

Built with skeletonized black steel construction, the AR-THJ is machined to match the exact dimensions of the AR-15 fire control pocket. The open-sided design gives you unrestricted access to the trigger group components, so you can make adjustments, test function, and evaluate geometry without repeatedly installing and removing the assembly from a lower. Flexibility is built in: the jig can be clamped in a standard bench vise or secured to a pistol grip for hands-on evaluation in different positions.

The included plastic block is a practical touch—it lets you safely dry-fire and cycle the trigger mechanism under spring load without risking damage to your hammer or the jig itself. Whether you're troubleshooting a stock trigger group, testing an aftermarket upgrade, or fine-tuning a custom assembly, this tool takes the guesswork out of AR fire control work and saves time compared to repeated install-and-test cycles in the receiver.

Key Features

• Skeletonized black steel construction machined to AR-15 fire control pocket dimensions
• Open-sided design for full access to sear, hammer, and disconnector engagement points
• Observe trigger function under normal spring tension without removal
• Vise-mountable or attachable to pistol grip for flexible positioning
• Includes plastic block for safe dry-firing without damage to hammer or jig

Specifications

Frequently Asked Questions

Is the AR-THJ compatible with my AR-15 lower?

The jig is machined to the exact dimensions of the standard AR-15 fire control pocket, so it works with any AR-15 trigger assembly. You're testing the group components themselves in the jig, not installing the jig into your lower receiver.

Can I use this jig to test aftermarket trigger groups?

Yes. The jig accommodates any trigger assembly designed for the AR-15 fire control pocket, making it ideal for evaluating performance and function of premium or custom trigger groups before final installation in your lower.

Do I need a vise to use it?

A vise is the most stable mounting method, but the jig can also be attached to a pistol grip if you prefer hands-on positioning or don't have a bench vise available.

What's the plastic block for?

The included plastic block allows you to safely dry-fire and cycle the trigger mechanism under spring tension without risking damage to the hammer or jig itself.