It's not cheap at all. It is efficient. You don't want to know what a hammer forging barrel setup costs up front.
Sent from my SPH-L720T using Tapatalk
Printable View
Approximately $2,000,000 FN Herstal has two of them. They are a front-end heavy investment, but once that investment is made they are a good value for a high-volume barrel producer.
I said I don't know "exactly" what cold hammer forging actually, specifically means. I didn't say I knew nothing on the topic.
Then you need to be more clear. Stating, "I've read it's just a cheap way of making barrels" sounds pretty uninformed unless you qualify the statement.
Obviously you're not ignorant on the topic. There are some videos on YouTube that show the machines in action. Let me see if I can find one for you.
Sent from my SPH-L720T using Tapatalk
I'm ignorant on what it actually is, but I have read about it's costs and applications.
I'm watching the videos now.
It seems like it's just a process of literally pounding the cold steel, which toughens the steel, but also changes it's shape. I have also read that it reduces stress points in the steel. Is there some sort of bore/rifling plug in the barrel when it is forged? I think I'm still confused as to what, exactly, hammer forging is meant to do. Create the rifling inside the barrel? How would pounding the outside of the barrel create rifling inside it? Create the barrel and the rifling at the same time?
https://www.youtube.com/watch?v=HrmWN0igJY0
A while back I posted links to an army analysis of Steyr process hammer forged barrels in M2, M14, and M16.
Pretty dramatic results, primarily smoothness (reduced fouling), life, and accuracy.
Short version: the Steyr process changes the crystal structure of the metal. Same reason forged lowers are stronger than billet.
I think some of the cheapness rep is old news from Remington trying a us competitor process with mixed results back in the late 70s early 80s.
Sent from my PRC-104 using phonetics
I can see in the videos that there are automated weights/hammers that pound on the outside of the barrel. I can see how that part of the process works. What I do not understand is how the rifling is getting cut, what is happening inside the bore.
Is there a 2nd part to the hammer forging process that is going on at the same time that can't be seen in the videos? Is there some sort of tool that is inside the bore and cutting the rifling at the same time as the forging process is happening on the outside of the barrel? Is the rifling cut after forging? Before forging?
A "mandrel" is a piece of metal that is the exact dimensions as the desired bore and rifling? So the bore is...bored, some base-line rifling is cut, and then the mandrel inserted and the hammer forging process begun? Or is the bore drilled over-sized, the mandrel inserted, and then the barrel is hammered into shape around the mandrel which then creates the rifling as the metal is formed around it?
ETA; If the mandrel is a "negative" of the desired bore and rifling, then making the mandrel must be incredibly important. For a 20" 5.56MM barrel, the mandrel would be a 20" long, .223/5.56MM diameter metal rod with raised, thin areas that create the rifling. If this is true, then making the mandrel would be incredibly difficult as it must be very rigid, very hard/stiff, with extremely precise tolerances.
It would then make sense that the final exterior barrel profile and the chamber would be cut after the forging process.
Any metal manufacturing process specialists that can chime in with better info?
O.k.....so how the hell is the mandrel made? I can't imagine how precise it has to be made, and how hard the metal is that it must be made from.
And wouldn't the rifling end-up being the tougher part of the barrel, instead of the raised surface? Or does the steel still flow enough to form itself in a uniform manner even when cold?