Barrel steels

[fourbore]

I was wondering what is a good source for steel to make muzzle loading smooth bore barrels. That is hollow stock. What I want is a mild steel that has a little better or equal strength and consistency as 18th to mid 19th century firarms. The initial goal might be a small cannon and next a big bore shoulder arm or a bigger cannon. I really appreciate a good source for raw hollow stock. I hope without creating a controversy. I have a lathe and mill with minimal tooling, nothing fancy.

I found this on Mc Master Carr: (1 3/8 OD, 7/8 ID)

1 3/8"

0" to 0.005"

7/8"

45,000

Stress Relieved

Rockwell B60 (Medium)

ASTM A513

a link:
McMaster-Carr

If A513 is adequate in strength what if anything can be said for the ID uniformity of the bore over a 36" length.

 

[M. De Land]

Green Mtn uses 1134 for muzzle loading barrels.

 

[fourbore]

I have been studing some other industrial suppliers and I have learned that A513 is a manufacturing tollerance. That is a good finish inside and out, athough good is relative. It is encouraging. I found 513 offered in four alloys including 4140 which I recognoze as modern barrel steel (medium strenght) and both 1020 and 1026 (mild). There must be more. Mild for steel is pretty strong stuff and more forgiving should I decide to braze. I will keep an eye out for 1134. I am quickly geting in over my head. Then virus bound, I got the time.

 

[okawbow]

I used 1026 for a .75 caliber smoothbore matchlock. Worked for me. Used a double load to test the barrel.

 

[user 34300]

I'd more concerned about how the tube was made than the alloy. If it is DOM with a welded seam you will find lots of advice saying not not use it. IF it is seamless tubing that is better. For a cannon with super thick wall it may not matter so much. The large bore will not develop much pressure.

For a shoulder fired gun I personally would not use mild steel DOM tubing. There have been reports of barrels made of it fatiguing over time and bursting.

 

[fourbore]

Well, I think the Mcmaster stuff is DOM. My other choices seem to be cold drawn CDS and hot rolled HRS both appear to be A519. it is a lot of numbers to review. You think, I should I be looking at CDS?

 

[billraby]

I don't think I would want to use any sort of tubing for a barrel. Scota has it right. If you want to make a barrel the best way to go is to use solid bar stock and bore it out yourself. Need some pretty nice equipment to do that. Which is the reason why not many people do it.

 

[M. De Land]

I was wondering what is a good source for steel to make muzzle loading smooth bore barrels. That is hollow stock. What I want is a mild steel that has a little better or equal strength and consistency as 18th to mid 19th century firarms. The initial goal might be a small cannon and next a big bore shoulder arm or a bigger cannon. I really appreciate a good source for raw hollow stock. I hope without creating a controversy. I have a lathe and mill with minimal tooling, nothing fancy.

I found this on Mc Master Carr: (1 3/8 OD, 7/8 ID)

1 3/8"

0" to 0.005"

7/8"

45,000

Stress Relieved

Rockwell B60 (Medium)

ASTM A513

a link:
McMaster-Carr

If A513 is adequate in strength what if anything can be said for the ID uniformity of the bore over a 36" length.

If I were you I would get a used barrel with a shot out bore and ream it out to what you want. The hole is already drilled and you will most likely have a barrel steel able to stand black powder pressure.

 

[sgtsquid]

If you are looking for materials like that, don't trust McMaster-Carr. Go to a metal supplier, even if it is hard to find one that will handle small orders. Let's just say they are not always honest about their specs. If you ask them, they will most likely tell you what you want to hear to make a sale, and then plead ignorance later. They have done that to me in the past.

Also I just read the specs on the link you posted, and it says it is meant for low strength applications. Then check out the conflicting info in the description:

Also known as mild steel, low-carbon steel is easy to machine, form, and weld. It's widely fabricated into parts that don’t require high strength, such as fixture clamps, mounting plates, and spacers. This material can be surface hardened with heat treating.
Tubes

• Yield Strength: See table
• Hardness: See table
• Heat Treatable: No
• Specifcations Met: See Table

 

[Pete G]

There's a big difference between heat treating and case hardening.

 

[M. De Land]

Well actually casehardening is the first method of heat treatment and does strengthen steel as well as harden it. All early cartridge guns where low carbon steel with a case hardened skin which leaves the interior malleable. Pre war Mauser and Springfield Bolt action rifles capable of handling psi in the 60 K range are case hardened low carbon steel that will stretch if the case is not thick enough. Alloy steel that hardens all the way through did not begin to appear in gun construction till about WWII when carbon, nickle,silcone,chrome and manganese was blended for strong, tough and malleable alloy steel both in barrel and receiver. It takes about .30-.40 percent ( that is part of one percent) of carbon to make a through hardenable steel alloy.

 

[Carbon 6]

Gee, I thought for sure someone would mention 12L14

 

[Stophel]

Oh, someone will... along with Remington shotgun barrels....

More frightening than the choice of steel, though, is someone making a gun barrel who has no idea what they are doing.

 

[Licespray]

Here’s a video of a friend making one.

He’s done barrels for centerfire rifles and muzzleloaders (just personal use)

 

[tomm9903]

I don't think I would want to use any sort of tubing for a barrel. Scota has it right. If you want to make a barrel the best way to go is to use solid bar stock and bore it out yourself. Need some pretty nice equipment to do that. Which is the reason why not many people do it.

As a gunsmith I would strongly recommend making it from a solid bar.

 

[tomm9903]

If you are looking for materials like that, don't trust McMaster-Carr. Go to a metal supplier, even if it is hard to find one that will handle small orders. Let's just say they are not always honest about their specs. If you ask them, they will most likely tell you what you want to hear to make a sale, and then plead ignorance later. They have done that to me in the past.

Also I just read the specs on the link you posted, and it says it is meant for low strength applications. Then check out the conflicting info in the description:

Also known as mild steel, low-carbon steel is easy to machine, form, and weld. It's widely fabricated into parts that don’t require high strength, such as fixture clamps, mounting plates, and spacers. This material can be surface hardened with heat treating.
Tubes

• Yield Strength: See table
• Hardness: See table
• Heat Treatable: No
• Specifcations Met: See Table

Speedy Metals is a good source for 4140 steel and they do small orders. Speedy metals.com

 

[M. De Land]

Here’s a video of a friend making one.

He’s done barrels for centerfire rifles and muzzleloaders (just personal use)

I've made half reamers for barrel chambers and reloading dies using the same configuration of bore that he shows. The trouble with this method is getting the hole straight as the boring tool is not self steering from the tip nor does it have a means of continual chip removal . A well bored deep hole will hold less than .010 run out in 28-30 inches I've read. The hole shown looks to have at least .025 and probably more as I could not see the dial integrations, run out which means the hole is curved. Turning the ends concentric does not solve the problem either as the bore still has a curve in it.
A deep hole bore self centers from the point and has continual swarf/chip removal from pressurized cutting lube pumped through the center of the bore to the cutting end. This keeps the chips flowing to the rear and out of the bore. The pressure has to be increased as the hole gets deeper to keep the chips from deflecting the bore nose. I've read .010 run out in 28-30 inches is considered quite good for the average barrel.
One would think that a bore with a curve would be a straight line tangent but it never is. It will usually show up as a serpentine curve. This can very often be viewed with the barrel centered in the head stock of a lathe and rotated at slow rpm. It can look like a jump rope down bore if crooked enough. That is the reason one wants to orientate a new barrel with the curve up at 12 O'clock so that both the front and rear sights can be centered in the dove tail slot for calm air zero in windage adjustment.
That does not mean a curve translates to inaccuracy but it does mean it needs to be considered in barrel orientation. Harry Pope would not bother to rifle a barrel unless it was pretty near perfectly straight and I don't believe any ever are perfect in this regard.