Cold Hammer Forged Barrels: How They're Made and Are They Worth It?

Cold Hammer Forged Barrels: How They're Made and Are They Worth It?
August 30, 2022 Edited March 28, 2023 17009 view(s)
Cold Hammer Forged Barrels: How They're Made and Are They Worth It?

The science poured into modern gun barrels is staggering, and lightyears ahead of the smoothbore muskets used by most patriots during the Revolutionary War. Today’s enthusiasts almost take that interior rifling for granted, despite the fact it imparts spin to the bullet, stabilizing it in flight and tightening groups at long distance. Creating those interior lands and grooves is no easy task, but when it comes to the process that delivers performance, reliability and longevity—without breaking the bank—cold hammer forged barrels are hard to beat.

There are five major methods of creating rifling. As technology marches on there will likely be more, but an examination of the other techniques helps underscore the advantages of a cold hammer forged barrel.

Inside of Rifle Barrel

 

Methods of Rifling

Cut Rifling

This is the oldest technique used and, as you might expect from its age, labor intensive and expensive. In this process a hook-shaped cutter is pulled or pushed through the barrel while simultaneously rotating at the rifling twist rate.

Each pass creates a single groove and, because there is always more than one, the cutter must go through multiple times. Alignment must be precise for each pass. Relatively little stress is imparted on the barrel, but lapping follows to remedy the minute imperfections common to cutting. It’s another step in an already lengthy and labor-intensive process.

When done right tolerances are squeaky tight, making them a popular choice in the serious long-distance shooter crowd. It’s not a procedure that lends itself to novice hands, however, or volume production. It takes skilled craftsmanship and tedious attention to eliminate performance-robbing variables, and as a result they are expensive. Experienced enthusiasts capable of printing mind-bogglingly tight groups at staggering distance may reap the full benefits, but today’s cold hammer forged barrels also win matches.

 

Broach Rifling

Broach rifling is similar to cut rifling, except grooves are created with a single pass of a metal bar wearing multiple cutting blades. The cutters are progressively higher in each “row,” with the last one gouging each of the grooves to their final, prescribed depth. The bar, obviously, must also rotate at the proper rifling rate for the barrel.

The process was once a popular, timesaving one for mass-produced firearms. It’s taken a back seat today because holding barrels to precise tolerance with this technique is a real challenge and the results are rarely match-grade. It’s still in use on some handgun barrels, however.

 

Button Rifling

A carbide tungsten button—really a bullet-shaped tool with the rifling pattern reversed and milled on its surface—is pushed or pulled through a barrel in button rifling. As it passes through the smooth barrel bore interior material on the sides flattens. For utmost in performance, stress must be relieved later.

Done right the results can be match grade, but those buttons are not cheap. They are also designed for a specific caliber and permanently affixed at a single rate of rifling. It’s a costly investment for manufacturers—one passed onto enthusiasts.

 

Cation Rifling

Leave it to chemists to create a barrel-making process using acid. A rod pushed through the barrel’s bore deposits acid where grooves are etched—at the proper rifling rate. The solution is allowed to dwell long enough to etch/remove metal and, depending on the preferred groove depth, it can require multiple applications.

The approach is still in its infancy and the jury’s still out on consistency, although early performance is encouraging. Variables include temperature, slight variation in steel alloy from lot to lot and different factors. It can, however, process material that defies other methods. Odds are good we won’t see cation rifling soon due to the expense, as well as the added challenges of hazardous material handling and storage.

 

Cold Hammer Forging

A cold hammer forged barrel starts life, so to speak, as a short and fat blank with a polished hole running through the center. A hardened mandrel of proper width (caliber) and rifling pattern—again reversed/inverted—is placed into the smooth bore. The pair go into a forging machine that compresses the steel against the mandrel, hammering it into final shape. The barely detectable external spiral patterns that remain on some barrels are imprints from those hammers at work. Some companies polish them out, however.

Cold hammer forges are also a significant investment for companies. However, when the process is done and the mandrel removed, the resulting barrel is the proper length and profile with rifling that is consistent and butter smooth. No lapping is required—a time and expense saver—although a stress-relief step often follows.

The process takes place at room temperature, despite the misleading “cold” terminology. There is a hot hammer forging process, but the equipment is even more expensive and the slight improvement in grain consistency hasn’t proven advantageous enough for a return on that investment.

Performance is impressive and consistent. Even serious long-distance shooters admit it’s not uncommon to encounter CHF barrels that perform close to or on par with good cut rifled versions. They outperform the skills of nearly every gun owner, especially when it comes to AR-15 chamberings, where the primary mission isn’t usually stretching the distance to 500 yards and beyond.

One of the biggest advantages of a cold hammer forged barrel is longevity, though. They thrive in nasty environments, survive abuse and last longer. The manufacturing process adds those enviable virtues with each strike of those hammers—strengthening the metal in a work hardening process employed by blacksmiths for centuries.

A chamber can be formed and barrel contour shaped at the same time. It’s a versatile approach that produces some of the most consistent barrels available today.

Cold Hammer Forged Diagram

 

Which One’s for You?

If long-distance is your passion and you home brew custom cartridges to print tiny groups in the next zip code, cut rifling is the optimum choice. Those who spend weekends punching paper at 1,000 yards know well, though, putting one on a favorite bolt gun is going to be an investment. Even with ideal pampering its lifespan will be a relatively short one in firearm years. Button rifling is a solid second choice, but not always the Holy Grail long-distance shooters dream about.

Cold hammer forged barrels, however, last longer and perform beyond the abilities of most AR-15—even AR-10—cartridges. High-volume shooters don’t need to worry about burning out an expensive barrel and, even if your passion is precision with your modern sporting rifle, the only detectable real-world difference you’ll experience is price tag.

[Bear Creek Arsenal recently invested in 2 state-of-the-art cold hammer forged machines in order to provide our customers with even better quality products at phenomenal prices. Check out our first selection of hammer forged products below!]

 

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Purdy Westover
September 1, 2022
thank you for the information .
Daniel Snyder
September 1, 2022
Thanks for all the knowledge you have given me,I like to learn something everyday.
Michael
September 9, 2022
This is awesome! Looking forward to seeing an upper in the 223 Wylde with 18” barrel come out in the hammer forged.
Robert
September 11, 2022
Definitely hope to see you expand the product offerings beyond the 5.56 NATO chambering in 16". .223 Wylde 10.5 / 11.5 / 16 / 20 300 AAC 10.5 / 11.5 7.62 x 39 10.5 / 11.5 / 16
Garreth Cumber
September 12, 2022
Great information it broaden my knowledge about barrel making.
Michael Springborn
September 30, 2022
I have gotten all but one caliber from you and that is the 350 legend, will get it soon, waiting for a sale. I really want to know if you are ever going to make a Winchester 264 or 300 mag lowers for AR 10. The 300 mag would be my next purchase if you ever make them. Would like it in the cold hammered process. Like your products have bought a few from you, and I am a loyal customer. Thanks, Mike
Harold Piskiel
October 4, 2022
Will your CHF Barrels be available as barrels, separate from uppers ?
Michael T
October 11, 2022
Any Idea when CHF barrels in .223 Wylde will be produced, if at all? Thanks!
George
February 9, 2023
Why wouldn't you just purchase a CHF barrel in a .556 (which handles higher compression rates) and simply enjoy shooting your lighter .223 loads through it?
Ralph Hernandez
October 18, 2022
In death article on Hammer Forge barrels. Never thought I would buy an AR 15 but I now own three of them and I would like to buy a fourth looking at a right side charge 16 inch A.R. 15 in 7.62 x 39. SKU# CR911N-SCH762CHB161109 but it is not offered in a 10” Handguard: Thanking you in advance; Ralph C.
Ray Palmer
December 6, 2022
I contacted you guys over a year ago about a 6.5PRC AR-10 Upper. Come on now! Where is it? Why aren't manufacturers making this upper. Isn't the cartridge designed to work in an AR-10? REAL QUICK- do you pin and weld the flash hider on you barrels or are they just screwed and torked. Need to know if I can put a comp on myself. Just had the misfortune of finding an old new Armalite A1 M4 AR-10 barrel assembly I got 35yrs that was removed to build a match gun. I had to have a gunsmith grind, mill and turn the compensator to find that it was pinned and welded. It had to be removed to be able to change to a DPMS barrel nut. I could have bought TWO of your upper assemblies for what I've spent on complete reciever, BCG, barrel nut, parts and tules.
Brandon francis
December 29, 2022
Will you be selling cold forged barrels separately. I have recently purchased one of your 7.62x39 in side charging and would.like to purchase a cold forged barrel
Robert
January 10, 2023
Will the new gen 2 side charging handle replace the old round knob on my 350 upper and how do I get one if it fits?
yarddog
January 21, 2023
So very happy that you guys made this investment, may God bless that you are rewarded many times over for it. You are my favorite patriotic company and I feel that CHF is a great investment for myself. Do you happen to make left-side charging AR's? This post was highly informative, thank you very much! Keep up the incredible work
Mike Kelley
January 31, 2023
Hope to see 8.6 BO barrels in various lengths. Will you be building uppers, guns and barrels for your current stable of AR10 calibers using CF barrels? ...from a loyal customer.
James Bice
January 31, 2023
Love the descriptions of the process used to make my ARs. Great job. Is there someone who can look at what I bought and give suggestions on what to buy next to make a different caliber AR.
Scott L.
February 1, 2023
Winchester has used the hammer forged method for decades on many of thier rifle barrells. It's not a new process just not common knowledge to most shooters.
Albert Cordova
February 1, 2023
I have been waiting for cost to come down ..I personally own 5 of your uppers with each one cycling %100 and have to speak on there ability to always run tight groups...I need one of these CHF barrels
vantine JR
February 2, 2023
Thanks for the informative article & pls keep them coming! I recently purchased a complete AR as a gift for my daughters birthday and also a 7.62 x 39 complete upper from BCA. Both I consider good/great buys & l’ll be returning for additional complete upper purchases in both 22WMR &22LR calibers. I’m not thrilled about the 22WMR upper only available in stainless to be honest. I am looking forward to the possibility of a CFH barrel for the 7.62x39 upper in due time and am curious about the possibility of cold forge hammered 22WMR barrels as well. Is it a process that lends itself well to .22 and .17 calibers? BEST REGARDS to all @ BCA in 2023 and beyond !!!!
Brian Anderson
February 9, 2023
Will you be doing the Glock barrels eventually?
Henry Woods
February 14, 2023
I am looking to purchase a 762X39 complete upper . What is the diameter of your barrels are they optimized for the .308 bullets or for the .310. I plan on hand loading soft point ammunition.
Charles Posey
February 15, 2023
I have several of your products. Never any issues. I plan on one of these hammer uppers. Thankyou for looking out for the little guy. Keep your powder dry.
Charles Posey
February 15, 2023
Thankyou for looking out for the Little Guys. I have several of your rifles. Well, uppers.I’ll own the hammer forged soon , i hope. I enjoy sticking with a company that sticks with US
Frank
February 18, 2023
When will you make a barrel for 6.5 Creedmoor and 308 that is hammer forged
Jack abner
February 18, 2023
I want to get my hands on the ported .308 barrel. When can I find one on a 20/22 inch stainless upper kit ?
Roger Krumbach
February 19, 2023
I've got one of your 350 legend uppers and it shoots great for the price
David Grace
March 10, 2023
I'm bummed. Right after I order from you guys you come out with a 7.62x39 hammer forged upper for 50.00 more. I wish I would have known.
Douglas Kennedy
May 10, 2023
are all BCA barrels cold hammer forged?
John
May 10, 2023
No not all are. Currently we have CHF in 5.56 Nato, 7.62x39, and coming soon will be the .308. They are located here: https://www.bearcreekarsenal.com/guns-parts/hammer-forged.html
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