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FIRING PIN PROTRUSION GAUGE Reviews & Ratings

BROWNELLS FIRING PIN PROTRUSION GAUGE FOR AR-15/M16

The Brownells Firing Pin Protrusion Gauge for AR-15/M16 is a simple but critical diagnostic tool designed to verify proper firing pin protrusion in AR-platform rifles. Correct firing pin protrusion is essential for reliable ignition and safe firearm operation. Insufficient protrusion can lead to light primer strikes and misfires, while excessive protrusion may cause pierced primers and potentially unsafe operating conditions.

Designed specifically for the AR-15 and M16 bolt assembly, this precision gauge allows armorers, gunsmiths, and firearm builders to quickly determine whether a firing pin falls within the acceptable operating range. It is particularly useful when assembling a new bolt carrier group, troubleshooting ignition issues, or inspecting heavily used service rifles.

Constructed from durable steel and compact enough to fit easily into any armorer's kit, this gauge provides a fast and reliable method for confirming proper firing pin function.

FEATURES

Measures firing pin protrusion on AR-15 and M16 bolt assemblies
Helps diagnose ignition and primer-related issues
Verifies firing pin protrusion falls within acceptable specifications
Detects conditions that may cause misfires or pierced primers
Quick and easy to use during assembly, inspection, or maintenance
Precision steel construction
Compact size fits easily in an armorer's toolkit
Ideal for gunsmiths, armorers, and AR builders

SPECIFICATIONS

Manufacturer: Brownells
Application: AR-15/M16
Material: Steel
Overall Length: 2" (5.1 cm)
Width: 1/4" (6.3 mm)
Minimum Protrusion: .028"
Maximum Protrusion: .036"

CUSTOMER INSIGHTS

AR builders and armorers often consider firing pin protrusion one of the most overlooked measurements in bolt inspection. Customers appreciate having a dedicated gauge that quickly confirms a firing pin is within specification, eliminating guesswork during troubleshooting. Many users keep this gauge alongside headspace gauges as part of a complete AR inspection and maintenance toolkit, particularly for high-round-count rifles, duty carbines, and newly assembled builds.

The Brownells Firing Pin Protrusion Gauge for AR-15/M16 provides a fast, accurate method for verifying firing pin protrusion within the recommended range of .028" to .036". Built from durable steel and designed specifically for AR-platform rifles, it helps prevent misfires, pierced primers, and other ignition-related issues, making it an essential tool for builders, armorers, and professional gunsmiths.

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1 Stars

Reviews Summary

The FIRING PIN PROTRUSION GAUGE is well-regarded for its utility and accuracy, especially among armoring professionals and hobbyists. However, some users noted issues with marking clarity and minor manufacturing flaws. Despite these shortcomings, it remains a valuable tool for checking firing pin protrusion efficiently.

What Reviewers Are Saying

Product Utility

75%

Many reviewers praise the tool for its practicality and efficiency in measuring firing pin protrusion, making it essential for AR-15 builders and for monitoring firing pin wear. It is highlighted as a necessary tool for both personal and professional use.

Marking Clarity

43%

Several users expressed frustration with the unclear markings on the tool's ends, which impacted usability. Some noted that the engravings were almost illegible, leading to misidentification of measurements. This concern suggests a need for better quality control in markings.

Quality Control Issues

43%

Reviewers indicated that despite the tool being functional, there are concerns regarding manufacturing errors, such as incorrect markings that were communicated as widespread in current inventory. This suggests that users expect more attention to detail from Brownells.

Value for Money

57%

Users frequently mentioned the product's affordability and considered it fairly priced, especially given its reliability in fulfilling its intended purpose. This indicates that it offers good value compared to other options.

Professional Endorsement

29%

Armors and professional users of the tool recommend it for its efficiency and time-saving capabilities. The endorsements from professionals underscore the tool's relevance in both amateur and expert settings.

Customer Photos & Videos

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Simple to use

Hard to find anywhere, out of stock everywhere.. finally back for a quick firing pin check, very easy

Would you recommend this? Yes, I would recommend to a friend

by RICHARD A. on July 01, 2025

Verified Purchase

Was this review helpful? 2

Great tool

Very handy tool for a quick pin check.

Would you recommend this? Yes, I would recommend to a friend

by STEVEN V. on May 16, 2025

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Was this review helpful? 2

Best guage on market.

Always use one at work now I bought my own for home.

Would you recommend this? Yes, I would recommend to a friend

by OTON V. on September 15, 2024

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Was this review helpful? 3

Quality gauge

Perfect for measuring min/max firing pin protrusion if you don't have a dial indicator handy.

by Anthony M. on February 18, 2024

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Was this review helpful? 3

Mr.D.

Excellent tool for what it was designed for.

by JEROME (. on January 01, 2024

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Was this review helpful? 3

Great for new builds & maintenance

A must have when building an AR-15 and for monitoring firing pin wear. A firing pin that exceeds the maximum bolt protrusion is unsafe and must not be used.

Time saver

Armorer for our dept, this tool saves time. Yes you "could" probably make one but why bother. Fairly priced & double checked specs are as marked.

Wrong Engraving

I took one star away because these should be marked and sold as a blem, because .028 side should say MIN. Instead they both were engraved MAX. It is still usable, and the numbers are correct, but it is a little aggravating, and Brownells is aware of this and told me that they can not swap it out because ALL of their current inventory (May 2024) has the same error. This should be noted on this page, and current stock sold at a discounted blemished price.

Would you recommend this? Yes, I would recommend to a friend

by Mike on June 07, 2024

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Was this review helpful? 7

Armorer

Very poorly marked ends, almost unreadable. Looks like a really poor attempt with a laser etcher. Should have been engraved.

by CH on November 13, 2023

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Was this review helpful? 2