forging a barrel

[steviejake]

hello, I bought Jon Laubach's dvd on forging a Flintlock Rifle Barrel and while informative and fun to watch it left me with more questions than answers. If anyone has forged a barrel could you help me out?
-it appears as though the skelp was cut tapered to give the breech end more mass but one of the first things they do in the video is taper it more without really explaining why.
-would the muzzle end be tapered also for a swamped barrel or would they just "jump" more mass into that end?
-I had no idea that the flats were hammered in. That makes sense that it would leave more material on the barrel by minimizing filing loss. He didn't explain how one straightens the barrel though. Is it done after the flats are finished with a file?
-The reaming bit seems easy enough to make (easy being a relative term here) but can you just put the barrel in a vice and put the bit in a hand drill and ream it freehand or does it all need to be held in some sort of jig? Would one use a lubricant with the reamer? Is this done before straightening the barrel?
-I understand annealing makes the barrel softer to work with (filing flats and reaming) but will it need to be rehardened when all the work is done?
-although not as authentic, wouldn't a gas forge make the welding process much easier?
-I'm not even going to ask about rifling yet.
Thank you for any help.
steve

 

[jerrywh]

I never forged a barrel but I have made several by hand from bar stock. The bores are first rough reamed with a long reamer. These reamers were usually made square and then twisted into a spiral about 12" or longer. Then the bore was reamed with a long [approx 8" long] square reamer with a wooden back. Shims were placed between the wooden back and the reamer. I have several of these and just used one to make a test barrel. The finish reamers only cut about .001 pr. pass and lots of cutting oil needs to be used on both type reamers. I mean lots. This is done on a boring bench and there are some photos of one in the book [ the muzzle loading cap lock rifle] by Ned Roberts. After finish reaming the barrel is straightened. There are at least three methods of straightening a barrel. I have a overhead barrel straightening press like was used in Belgium in the 1800's. Wrought iron or mild steel will galled easily if not well oiled and if you try to take too deep a cut. A modern reamer with a long shank welded on will save you a lot of work for the long reamer.
The outside should be finished before straightening also. The outside of octogon barrels was [usually] ground on a grinder in a fixture. illustrations of this can be seen in the book entitled [the Age of firearms.] and in the Diderot Pictorial Encyclopedia of Trades and Industry.
When and if you finish one you will be plenty willing to pay $1000.00 for a good barrel.

 

[rich pierce]

All good advice I'd just add that you'd not want to harden a ML barrel. Ideally you'd be using mild steel or wrought iron. So far as forging with a gas forge, sure, it would be easier. But normally anyone forging a barrel is looking to do things the hard and traditional way.

 

[jerrywh]

There is a very important factor in forging a barrel. It is very important to use a neutral flame or fire. A reducing fire or flame will cause the iron to take on carbon and transform the iron into high carbon steel as in crucible steel. A oxidizing flame or fire will cause the iron to burn rendering is useless. I have forged dozens if not hundreds of gun parts including locks. The fire is very important.

 

[TARL01]

I suggest you get "Hand Rifling a Muzzlle Loading Rifle Barrel At Home" by Mark Wagner. It's only about 50 pages or so and is only about 7 or 8 bucks. Besides a "how to" on reaming and rifling, it shows you how to make a rifling bench and how to make homemade rifling tools. Lots of pics and diagrams. Brownells has it.
Woody

 

[steviejake]

thank you for all the information. I am not sure what you mean by overhead straightening press. Could you elaborate on the ways the barrels were straightened. the dvd shows how to make the square-twisted reamer. Also, what did you mean you make barrels by hand from bar stock? you get the appropriate size round stock and bore it out? Thanks again, steve

 

[jerrywh]

Yes. I just buy a round bar and machine from there.
Here is the barrel straightening press. In the early 19th century these type were hung from the ceiling and the worker looked thru the barrel as he straightened it. Looking thru the barrel one can tell by the concentric rings of light if it is straight or not. You can look up barrel straightening on the web. Here I am in the act of straightening a double 28ga. set of barrels.

 

[steviejake]

wow, that's quite a machine! thank you so much for posting pictures of it. Any idea as to how one would straighten a barrel who doesn't have access to such a machine. I just want to know that if I start this project that I won't hit any impossible roadblocks. again, thank you, steve

 

[steviejake]

btw, is all barrel straightening done while the barrel is cold?

 

[jerrywh]

I never heard of a barrel being straightened hot.
It is impossible to heat a barrel to a high degree without warping it some. I have heated barrels in a temperature controlled oven that were bedded in vermiculite to 1500° and they still warped a tiny amount. If the heat was completely even throughout the furnace and the temperature raised very slowly and lowered very slowly the barrel theoretically would not warp if it had no stress to begin with. That is extremely hard to accomplish. I have kept one to no more than .010. That is the best I could do. I have experimented with this stuff for years.
Straighten at room temp. Rifle barrels are easier than shotgun barrels.

 

[rafterob]

There is a pretty informative book on primitive means of rifle building titled "Guns and gunmaking tools of Southern Appalachia : the story of the Kentucky rifle / by John Rice Irwin."

 

[jerrywh]

basicaly it's just a screw press.