6" diameter Cannon in progress

[338sniper]

steel has a tensile strength that is around 50% higher then cast iron

 

[IndyGunworks]

I went to the one web site and the rule of thumb dealing with wall thickness to bore size refers to CAST cannons. Black powder is low pressure. My dad made his golf ball cannon out of 4" steel and it has a 1 3/4" bore, that's only about a one inch wall. Do any of you have specific reference of specs using modern solid steel not cast using a liner. Here's a copy of what the website said, where does it say it applies to solid steel(not cast/lined) barrels.






All reproduction barrels manufactured after March 1, 1986 must have pictures of the liner and breech plug before and after welding. No reproduction barrel shall be approved after March 1, 1986, that does not have one caliber’s thickness of metal surrounding the bore at the breech unless approved by Artillery Ordnance Officer. (See figure 10.2 for example.) Liner may be affixed by casting barrel around the liner or by other approved methods such as bonding with high strength adhesives. The method of locking the liner in the barrel shall be approved by the Artillery Ordnance Officer. The gun and its crew must pass the inspection specified in Section 18. A gun crew shall consist of a minimum of four members of the organization. Effective 1 February 1996, all artillery pieces must be originals or full-size, exact replicas to be approved.

Let's consider a 3" 50 cannon, most of the chamber for it is in the barrel and it ( the barrel part of the chamber in front of the breech ) is not 9" in diameter and I guarantee that it operates at several times the pressure of the black powder cannons.

steel has a tensile strength that is around 50% higher then cast iron

You should go over to that board and ask this question. the short of it is YES, things can be done differently with steel and still be safe, but the safety recommendations are there for a reason. Not all steel is created equally. It sounds like you already know what you want to know so nothing else I can say is going to change anything. Just do your homework and make sure its being done with safety as the number 1 priority.

 

[338sniper]

INDYGUNWORKS

You say that DanB's, 7" piece of steel tubbing with a plug pressed and welded into it, sounds "fascinating and well buit". That's only 2" sidewalls with a 3" bore?

yet a solid piece of steel bored out doesn't sound safe?

please explain?

 

[30calmachinegunner]

The reason is that people like to sound more knowledgeable then they actually are on a subject. I'll wager I've been working on guns and machining steel longer then most of these detractors have been alive and if ANYONE thinks a welded plug in the end of a piece of tubing is stronger then solid machined steel lets have a wager, I can use the money to finance my next projects.

In fact I'll make any wager you want that using black powder(cannon grade) and short of welding the end of the barrel up you can't blow the solid steel machined barrel

 

[IndyGunworks]

INDYGUNWORKS

You say that DanB's, 7" piece of steel tubbing with a plug pressed and welded into it, sounds "fascinating and well buit". That's only 2" sidewalls with a 3" bore?

yet a solid piece of steel bored out doesn't sound safe?

please explain?

because he was explaining the methods of making the cannon in a mannor that I understand to be the correct way to build a cannon.

Its not so much the walls of the barrel that matter its the walls around the breech. that's all I have to say on this as I am not even close to an expert on this matter, I wasn't trying to call anyone out and clearly you think I had it out for you. You can do what you want. I only know enough about this topic to know what not to do. If you want to really find out an answer to your question, and not just try to call me out and put ME on the spot to answer it then you should go over to that grey beard cannon board and ask the question there. You will be getting answers from people that have building cannons for a living for 30 plus years on some cases. they will be able to explain it to you in a way that you wont feel the need to have them explain themselves any further.

 

[338sniper]

I wasn't trying to be a prick or hard headed. I was simply asking for something to back up your post or gives more info that shows where using solid steel follows the same "rules of thumb" as cast with a liner. If I didn't want the feedback or input I would not of made the post. It was not my intent to question your comment but more to question where the info comes from.


Please keep keep the info and feedback coming

 

[IndyGunworks]

I wasn't trying to be a prick or hard headed. I was simply asking for something to back up your post or gives more info that shows where using solid steel follows the same "rules of thumb" as cast with a liner. If I didn't want the feedback or input I would not of made the post. It was not my intent to question your comment but more to question where the info comes from.


Please keep keep the info and feedback coming

best I can do is quote people that know more than me.

As stated in our stickies above... the Nationally recognized standards by cannon shooters recommend the wall thickness at the chamber be equal or greater than the bore diameter. Including behind the chamber. Admittedly not all period pieces did so but they were close enough to earn our respect... and they also kept a round count & retired fatigued pieces. Some failures were considered acceptable in combat... in modern use, there is zero tolerance for failures.
I would apply these same standards to thunder mugs or signal cannons. I would judge any prospective purchase by how close it came to conforming. As we often say here... do not forget that a signal cannon is your legacy. Consider that your heirs may not load it as carefully as you do. Don't allow your legacy be an accident.

A piece bored from solid, has no seam to fail.

Any gun can be blown up. The US Army destroys captured ordinance by improper loading. This common practice was continued in Iraq, for overrun enemy positions, so the assault could move forward without worrying about leaving active artillery in your rear.
All firearms including signal cannon ARE dangerous. They would not be any fun if they weren't. We control the risk to the greatest possible extent by best design & careful technique. It starts with recognizing the forgoing & expending the necessary efforts to learn proper loads & drills.


nobody is saying it would be UNSAFE. and its not about wall thickness anywhere but the breech. while you are interpreting it as only applying to cast iron, my experience from reading what some of the die hard cannon builders are saying is that it doesn't matter what its made out of its one caliber wall thickness all the way around the breech regardless. they don't even allow full cast iron guns in any of the national organizations. they have to be sleeved with a 3/8 thick seamless tubing and even then the one caliber rule still applies

 

[338sniper]

This is a 36" long piece of steel bored out 33" deep. That leaves 3" in the back if the breech. Sure it will be rounded off some but I don't imagine it will be much. The side walls near the breech which makes the walls appx 1.75" thick. The sidewalls will be turned down more on the muzzle end than the breech end due to the contour of the cannon. This is not being built to shoot everyday (maybe 4 or 5 times a year at the most) and powder is to expensive to load it with 1lb of black powder.

how much powder do you pack in yours?

 

[IndyGunworks]

I will be shooting off of the recommended amount.... I believe (have to double check) its 2oz of cannon grade BP per inch of bore. that's close to 5 oz in my case. I think that's for firing with ammunition though. I plan on normal blank charges being 8oz MAX anymore than that and I will probably be throwing powder out of the end of the barrel and wasting it. use MUCH less if you are not loading with cannon grade, or if you are using wadding.

I am sure like anything else these safety standards are WAY overdoing it, but we are dealing with a controlled pipe bomb and I have no intentions of pushing the limits. I will certainly never fire a full pound of powder.

 

[338sniper]

I'm thinking a New Year's Eve test fire.



Anyone wanting to put any wagers up on life insurance?

Everyone throw in $100 and make your bet live or die?

 

[338sniper]

 

[Caleb]

is that aluminum?

 

[338sniper]

No, STEEL

 

[IndyGunworks]

What are you going to use for the cascabel?

 

[30calmachinegunner]

2" trailer ball modified and TIG welded on

 

[30calmachinegunner]

 

[IndyGunworks]

Looks amazing... How long is it?

 

[30calmachinegunner]

36" long

 

[30calmachinegunner]

Number 2(or4), did it a little different

 

[indy1919a4]

30cal, those barrels look very nice, How much do those Steel barrels weigh????? And do you know how much weight you cut off of the original steel bar??? And if I can ax one more question how many hours is spent in the actual milling?????