Real evidence supporting hammer forged barrels????

[hammonje]

Is there any real evidence stating the superiority of hammer forged barrels over regular AR barrels??? I can get 1 MOA out of many of my ARs at 1-200M. These are standard weight barrels.

Just wanting to know if the cost is worth it and am looking for data, not conjecture. Seems the barrel weight would have more to do with accuracy over hammer forging.

Let me have your experiences.

[Whootsinator]

I don't think many people who actually know what they're talking about even bother arguing that hammer forged barrels are more ACCURATE/PRECISE than barrels with cut rifling. Usually their argument is that they are MORE DURABLE/TOUGHER than barrels with cut rifling.

[rsgard]

While not specific to barrels there is plenty of evidence on the net on hammer forging and how it affects metal. One could infer that any pros or cons would also apply to barrels.

Just from a quick browse it looks like hammer forging deforms the crystalline structure of metal to the shape of whatever is being forged. I would guess this means more strength by having a solid crystalline structure over any form of cutting which would interrupt the grain of the metal.

The above may be completely wrong but its what i picked up from 5 minutes of browsing a couple of reference materials online. The actual difference between barrel types is not something i can comment on but the reasoning behind hammer forging is solid.

[Belmont31R]

Hammer Forging

Again, it was the demands of war that was responsible for the development of this process - only it was done by the other side. Hammer forging was developed in Germany in 1939. Here a drilled barrel, rather than being reamed, is honed to give it a very fine interior finish. Then it is placed on a tungsten carbide mandrel that has the entire rifling pattern ground in relief into its surface. The barrel/mandrel combo is then placed between two opposing power hammers and rotated. The hammers literally beat the barrel into the mandrel’s pattern. I’m told a barrel will actually grow around a third of its length during this process. It usually takes around three minutes for the rifling process to be completed. As you would think, this method produces tremendous stresses in the barrel that have to be relieved through heat treating.

The advantages of hammer forging is the fact that the interior finish is very good, and the bore surface becomes work hardened in the beating process. The result is a very durable, long lasting barrel. Modern hammer forging has progressed to the point that even the chamber can be included in the mandrel pattern. These machines are very large, complex, and expensive however. So the small custom barrel shops are pretty much eliminated from using them.

Additionally, some say that the induced stresses are so severe in this process that they never can be entirely eliminated. As a result, the bench rest crowd won’t touch a hammer forged barrel. However, I can’t help but wonder how valid this belief actually is, and whether anyone has actually tried it. Remington barrels, which always had a reputation for accuracy, used to be hammer forged, including those used in the XP-100. I know I always had excellent results with original XP barrels. Indeed, in Europe, hammer forging is the standard. Sako, Tika, H&K, Steyer, and Sauer all use hammer forged barrels. I’d hardly call their products junk.

http://www.lasc.us/RangingShotBarrelMakingFeature.htm


http://technology.calumet.purdue.edu...gedBarrels.pdf


http://technology.calumet.purdue.edu...gedBarrels.pdf

[hammonje]

Thanks for the information.

[Stickman]

Is there any real evidence stating the superiority of hammer forged barrels over regular AR barrels??? I can get 1 MOA out of many of my ARs at 1-200M. These are standard weight barrels.

Seems the barrel weight would have more to do with accuracy over hammer forging.

Thats like asking if you can fit more apples in a Ferrari or a Corvette. While you can use both for hauling apples, its not really the main reason most people buy them.

CHF barrels are known for durability and longevity, with good accuracy being a bonus. Military testing has shown the hammer forged barrels hold up longer.

[e1harris]

To my understanding, there is no question about the quality of Hammer Forging when it comes to the "toughness" of the material.

My only question as of late. Can somebody explain to me how Chrome Lining may negate the benefits of having a Hammer Forged bore?

What I really mean is, "Is there a difference in the bore between a cut or forged barrel when you take chrome lining into consideration?"


ETA:
I got myself thinking about it. Is the "increase" in accuracy of a CHF a resonance thing? I mean, I know it's not going to be "on par" with a stainless barrel. But surely the bore of a CHF vs Cut barrel are the same because of the Chrome Lining.

[120mm]

To my understanding, there is no question about the quality of Hammer Forging when it comes to the "toughness" of the material.

My only question as of late. Can somebody explain to me how Chrome Lining may negate the benefits of having a Hammer Forged bore?

What I really mean is, "Is there a difference in the bore between a cut or forged barrel when you take chrome lining into consideration?"

ETA:
I got myself thinking about it. Is the "increase" in accuracy of a CHF a resonance thing? I mean, I know it's not going to be "on par" with a stainless barrel. But surely the bore of a CHF vs Cut barrel are the same because of the Chrome Lining.

There are pry smarter people than me on this, but barrels wear out most quickly in the throat and gas port. The underlying material is key in how quickly these two places wear.

[RyanB]

They ought to be nitriding barrels anyway, as the chrome burns off.

[variablebinary]

They ought to be nitriding barrels anyway, as the chrome burns off.

It makes no sense to go CHF.

Nitride CMV barrels makes much more sense than going CHF if you don't already have a CHF pipeline in place, which most don't.