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November 5th, 2021

New Brownells AR Build Resource Site with How-To Videos

Brownells AR15 AR builder online how to build guide videos upper lower trigger

In the face of growing online censorship across many popular social media sites (such as YouTube), Brownells has launched a new online resource to help customers build their own AR-15 rifles at home. Hosted at Brownells.com/HowToBuild, the new web page features step-by-step, interactive videos. Featuring Brownells Gun Tech Caleb Savant, the videos show the AR-15 build process with easy-to-follow directions and expert advice. There are currently four AR Build videos: Introduction, How to Build Your Lower, How to Build Your Upper, and Troubleshooting Guide. See all videos at: Brownells.com/HowToBuild.

Access New Brownells AR Builder Video Resource Page »

Each of the videos have an easy search button on the upper left-hand corner, allowing viewers to navigate to specific parts of the video. This will help viewers access key parts of each video and find the information they need. For example, the Lower Video has specific sections on trigger and buttstock installation. There is also a video on how to properly test fire and troubleshoot an AR-15 once it’s built.

Brownells AR15 AR builder online how to build guide videos upper lower trigger

In addition to the instructional videos, Brownells’ AR Builder Site also provides links to all the parts, tools, and accessories required to build an AR-15 rifle. There are specific links to uppers, lowers, triggers, grips, buttstocks, bolt carrier groups, handguards, barrels, gas blocks, muzzle brakes and more.

Brownells AR15 AR builder online how to build guide videos upper lower trigger
Brownells AR15 AR builder online how to build guide videos upper lower trigger

“Several social media platforms have banned videos and other content showing how to build firearms,” said Brownells V.P. of Marketing Ryan Repp. “Because of Brownells’ long-time support of the Second Amendment and individual freedom, it made sense for us to create a professionally-produced video and resource center to assist rifle builders of all skill levels make the rifle of their dreams in the comfort of their own home or workshop.”

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November 5th, 2021

Colt Issues Safety Recall for AR-Type Rifles Made in 2021

Colt MSR AR AR15 safety recall double fire trigger issue

Colt has issued a Recall for certain Colt AR-type rifles made in 2021. Here is the official Recall Notice:

COLT’S Manufacturing LLC (“Colt”) has recently discovered a potential safety issue with certain Modern Sporting Rifles (“MSRs”). Colt is voluntarily initiating a recall to protect the safety of its customers because, under certain conditions, it is possible that some of these MSRs may discharge a second round when the trigger is released when there is a live round in the chamber.

For more information go to ColtRepairMSR.com

Colt is committed to the highest standards of quality and customer satisfaction. In keeping with that commitment, during routine quality testing, Colt discovered that hammers that do not meet Colt’s specifications were installed in certain MSRs that were manufactured beginning on March 5, 2021. The issue will be corrected by replacing the hammers in affected MSRs.

The recall only covers a portion of MSRs manufactured beginning on March 5, 2021, and includes the following models: AR15A4, CR6700A4, CR6920, CR6920-EPR, CR6920MPS-B, CR6921, CR6921-EPR, CR6933, CR6933-EPR, CR6960, LE6920-EPR, LE6920MPS-B, LE6920-OEM1, LE6920-OEM2, LE6920-R, LE6933-EPR, SP633784, LE6920SOCOM.

Chart lists all the serial numbers for those models that may potentially be subject to the recall:

Colt serial number recall

Model Marking and Serial Numbers

AR-15 A4: CAR022851 – CAR023250
CARBINE: CR036354 – CR099599
CARBINE: CR713001 – CR722100
M4 CARBINE: CR716801 – CR721500
M4A1 CARBINE: CR021580 – CR022024

To prevent the possibility of death or serious personal injury, Colt advises anyone who has purchased a Colt MSR since March 5, 2021 to stop using it immediately and visit ColtRepairMSR.com or call Customer Service at 1-800-971-3216 to see if your specific MSR is affected. Please note: Not all MSRs within the serial number range in the above chart are subject to this recall and this website offers easy, step-by-step instructions to determine if a particular MSR is affected.

Customer service agents will assist anyone who needs additional help. Our expert craftsmen are ready to upgrade all affected MSRs at our West Hartford, CT headquarters.

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November 5th, 2021

Guide to Gun Metals — What You Need to Know

Sweeney Guide to Gun Metal

4140, 4150, 316, 17-4, 6061, 7075-T6 — What is the significance of these numbers? No, they’re not winning lottery numbers. These are all designations for metals commonly used in firearm and barrel construction. 4140 and 4150 are carbon steels, with 4150 often used in mil-spec AR15 barrels. 316 and 17-4 are grades of stainless steel. 316 is “marine grade” stainless, while 17-4 has 17% chromium and 4% nickel. 17-4 is a harder steel used in barrels and receivers. 6061 and 7075-T6 are aluminum alloys. 6061 is “aircraft grade” aluminum, often used for rings and trigger guards, while 7075-T6 is a much stronger, heat-treated aluminum commonly used in AR15 uppers.

Sweeney Guide to Gun MetalYou can learn about all these metals (and more) in the online archives of RifleShooter magazine.

Written by Patrick Sweeney, RifleShooter’s Guide to Gun Metal summarizes the primary types of steel and aluminum used in gun and barrel construction. Sweeney explains the nomenclature used to define metal types, and he outlines the salient properties of various steel and aluminum alloys. This is a useful resource for anyone selecting components or building rifles. We recommend you print out the page, or at least bookmark it.

Metals by the Number
The number system for steel classification came from the auto industry. Sweeney explains: “The Society of Automotive Engineers uses a simple designating system, the four numbers you see bandied about in gun articles. Numbers such as 1060, 4140 or 5150 all designate how much of what [elements are] in them. The first number is what class—carbon, nickel, chromium, and so forth. The next three numbers [list other elements in the alloy]. 4140, also known as ordnance steel, was one of the early high-alloy steels. It has about 1 percent chromium, 0.25 percent molybdenum, 0.4 percent carbon, 1 percent manganese, around 0.2 percent silicon and no more than 0.035 percent phosphorus and no more than 0.04 percent sulphur. That leaves most of it, 94.25 percent, iron.”

Aluminum Alloys
Numbers are also used to differentiate different types of aluminum alloys. Sweeny writes: “Aluminum is used in firearms in two alloys: 7075 and 6061. 6061 is commonly referred to as ‘aircraft aluminum’ and has trace amounts of silicon, copper, manganese, molybdenum and zinc. 7075 is a much stronger alloy and has markedly larger amounts of copper, manganese, chromium and zinc.” 7075 Aluminum has significantly better corrosion resistance, and that’s why it is used for AR receivers. The “T6″ you often see appended to 7075 refers to a heat-treating process.

Aluminum (or “Aluminium” in the UK) is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal. Aluminum is the third most abundant element, and the most abundant metal, in the Earth’s crust. (Wikipedia)

Aluminum alloy table chart Silicon Maganese Zinc Copper Magnesium

To learn more about the metals used in your firearms’ barrels, rings, receivers, and internal parts, read Sweeney’s article in RifleShooterMag.com. Taking the time to read the article from start to finish will expand your knowledge of metal properties and how metals are chosen by manufacturers and gunsmiths. CLICK to Read Guide to Gun Metal.

Story Tip by EdLongrange. We welcome reader submissions. Aluminum Alloy chart courtesy AluminiumDesign.net.
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