New member checking in AGAIN with need for cannon project advice/MORE questions

[Part 77]

Hello all,
I found this forum while searching for black powder cannon information. It was linked from the Practical Machinist site. So far, I have learned a lot on the FAQ pages and the Sticky pages here.
I will be building a 1/4 scale roughly based on a 3" Ordnance Rifle and want to run some thoughts by the experts. I will use 2 1/2" round 1144 Stress Proof, bored 3/4", overall length 18" +/-. I plan to taper the OD from 2 1/2" to 1 3/4" at the muzzle. The taper will start 3" ahead of the chamber, meaning that the wall thickness over the chamber will be 7/8".
While shopping online at MetalsOnline.com, they advertise 1144 Stress proof "Or Equivelent". Any here one vouch for them and their "Or Equivalent " policy? In other words, will they ship material with the same 100,000 PSI yield strength?
Any advice or suggestions are appreciated. Thanks in advance.

[Double D]

Some one help me here, but if I remember some years ago LaSalle Stress proof 1144 was highly recommended for gun barrels. Then after some barrel failures  it was found to have issues with inclusions and is no longer recommend for gun barrels.  Any body else have remember something about this.

Medium carbon steel and requires special treatment for welding. There are special warning from Lasalle about welding stress proof. Mechanical properties are reduced and welding is not suggested.  LaSalle says because of the high carbon, manganese and sulfuer contact Strees proof is not considered a weldable material.

1018 is a better steel for cannon barrels. 

18 inches of 1018 will go $60.30 from online metals,  $27.47 from Speedy metals http://www.speedymetals.com/ps-711-96-2-12-rd-cold-finished-1018.aspx.  Of course shipping is extra.

[RocklockI]

Welcome Part 77 !

[GGaskill]

I would go with the 1018 cold rolled (if you are going to use the as rolled finish) or 1020 hot rolled (get this a little oversize as it is not truly round and the outer surface needs to be removed.)  They aren't as strong but are easily welded and strong enough.

[Part 77]

This is exactly the type of advice I was hoping for. What pressures are created by black powder? Can anyone be more specific than "strong enough" in describing 1018? What is it's yield strength? I assumed the listed specs on 1144 was a good thing (more is better) but am not a "steel " guy. I didn't know about it's welding unsuitability and plan to have the trunnions welded. Maybe I'm being overly cautious, but I know the man who's daughter was nearly killed on July 4th in Littlerock, WA when a home built cannon blew up 3 or so years ago. A young boy was killed in the same catastrophic failure.

[Double D]

This is exactly the type of advice I was hoping for. What pressures are created by black powder? Can anyone be more specific than "strong enough" in describing 1018? What is it's yield strength? I assumed the listed specs on 1144 was a good thing (more is better) but am not a "steel " guy. I didn't know about it's welding unsuitability and plan to have the trunnions welded. Maybe I'm being overly cautious, but I know the man who's daughter was nearly killed on July 4th in Littlerock, WA when a home built cannon blew up 3 or so years ago. A young boy was killed in the same catastrophic failure.

I have been trying for some time to get a copy of the police report on that cannon, what caused it to fail, what was it made of, what was used as propellant, etc.

[Part 77]

Double D,
I don't have any particular information. The man I mentioned works for the same company that I do. I will do some asking around to see what I can learn.

[Double D]

Double D,
I don't have any particular information. The man I mentioned works for the same company that I do. I will do some asking around to see what I can learn.

I don' mean to sound rude, I am interested in the anecdotal information, what I would really like to see is the scientific analysis and see what really happened.

[dan610324]

welcome here part 77
there is lots of knowledge and experiance here among the board members so its very good that you found this place before you started to build your cannon .
its just a pity that you wasnt here a month or so ago when we had a new member here showing up some "barrels" he built , I had a few not so kind words to say about them ( not kind but true ) as they was more pipe bombs than barrels in my eyes .
he couldnt handle the criticism and we didnt hear more from him , he would sure have needed to read some of the words in your last post here .
Im not the right man to try to straigten out the question marks here as I dont know the american steel qualities good enough , but Im sure you will have ansvers to your questions as soon as the right people reads them .
and once again welcome here

edit
you was too quick for me guys  so it wasnt in your last post here but in your second now

[GGaskill]

What pressures are created by black powder?

Pressures are determined by a number of factors.  In the case of black powder muzzle loading cannons, shot weight, charge weight, bore diameter, and powder granulation are major factors.   For any given bore size, more powder increases pressure, heavier shot weight increases pressure, finer granulation increases pressure.  For a given charge weight and granulation, smaller bore size increases pressure.  The factors that increase pressure work together so that heavier charge weight and heavier shot weight increase pressure more than just one or the other.  I guess what I am trying to convey is that one cannot quote some number as "black powder pressure" for all or even many circumstances.  This is the same as smokeless powder cartridge reloads; pressure is not a factor of smokeless powder but a function of all the factors combined.  All that being said, I use 20,000 PSI as chamber pressure when doing calculations.

There have been experiments made with heavy wall cylinders plugged at both ends and filled with black powder and touched off.  The results of this experiment were reported as the tube acted like a ground bloom (firework) with the fire coming out of the touchhole.  With thinner wall tubing (like ordinary water pipe), you would have a pipe bomb with this combination.  If you want to understand why you will never see anyone recommending water pipe as cannon material, look up water pipe specifications on the Internet.  The strongest is the smallest and it is less than 1000 PSI.


Can anyone be more specific than "strong enough" in describing 1018?  What is it's yield strength?

1018 has a yield strength of 57,000 PSI according to at least one source on the Internet.  There are many sources and I recommend you look it up yourself and evaluate the source as well as the number.  Keep in mind that the numbers are general and any given piece of steel may be stronger or weaker, although it shouldn't be significantly weaker if it really meets the standard for 1018.  This uncertainty is one reason why real world engineering projects are designed with safety factors.

[BoomLover]

Welcome, Part 77! Glad you found us here, before starting your build. Mucho Info available, and lots of guys to give a helping hand.....have fun, but as you already know, being safe is the reason you can have fun! BoomLover

[Victor3]

Some one help me here, but if I remember some years ago LaSalle Stress proof 1144 was highly recommended for gun barrels. Then after some barrel failures  it was found to have issues with inclusions and is no longer recommend for gun barrels.  Any body else have remember something about this.

 I was considering 1144 for a barrel years ago due to its high tensile & yield strength (and after all, it's "Stress Proof"  ).

 After some research I decided against it. It resists distortion and fatigue well along its length in applications like shafts and such where it tends to bend and twist, but doesn't perform near as well in the transverse for some reason. IIRC it has to do with the special process used when the bar is drawn during manufacture that form its grain structure.

[Part 77]

Thanks all for the open welcome and information!
GGaskill,
I had not found that specific type of info in the FAQ or tacked pages on this forum. It is much appreciated.

Happy Memorial Day!

[Part 77]

Double D,
I don't have any particular information. The man I mentioned works for the same company that I do. I will do some asking around to see what I can learn.

I don' mean to sound rude, I am interested in the anecdotal information, what I would really like to see is the scientific analysis and see what really happened.

Double D,
No problem...I assume you mean you are not interested in the anecdotal info, but actually the scientific anlysis. The police report wouldn't have more than the general details. I suppose there is ongoing litigation and any "official" report may never be publically available. That being said, the injured woman's father may know some factual details. I will share what I can.

[Double D]

The initial police report would be a summary.  The completed investigative report would have everything.  If any criminal litigation is pending the report may not be available yet.  If civil litigation is pending, there also may be some restrictions on information release.   I'm not interested in the whole report, just the analysis of the cannon.

Depending on what Washington's FOIA laws says all or parts or none of the entire report may be available. Police reports are not always available.  

The problem with the anecdotal, is that it is second hand and often inaccurate.  Not purposely inaccurate. Some one says he thinks the cannon was loaded with apples, and it is later passed on as the cannon was loaded with apples .  Then later it's proved it was loaded with oranges. The apple issue lingers and on the internet we know the problem with that.  Conspiracy theories! A bit melodramatic, but you get idea.  

We are still interested in the anecdotal as we can learn from that  also.  

[Frank46]

Some tears back there was a rash of blown barrels in both smokeless and black powder cartridges which was pretty well documented in "The Black Powder Cartridge Rifles" magazine. I bought the 3 volume set from "Precision Shooting" also some years back. I'm not a engineer or metallurgist by any stroke of the imagination. Bottom line is that don't use it. Stressproof 1144 I believe was specifically mentioned. The reason it was used was it was easily machined and rifled. I think  a ASSRA member had a single shot rifle barrel rupture on him as one instance. Better off with 1018 and no worries about wether a boom or kaboom will result when fired. Frank

[Part 77]

I'm unsure of my scaled dimensions (muzzle diameter, breech end diameter, location of trunnions, etc.) for a 3" Ordnance rifle barrel. Does any one have a link or diagram of the specs? I have found references of a 69.5 inch "tube" length and another article mentions a 72" barrel. Thanks again!

[Cat Whisperer]

This is exactly the type of advice I was hoping for. What pressures are created by black powder? Can anyone be more specific than "strong enough" in describing 1018? What is it's yield strength? I assumed the listed specs on 1144 was a good thing (more is better) but am not a "steel " guy.
...

If you're comparing the two, 1018 and 1144, it is not the yield/tensile strengths that are important in CANNONS.  What is important is the steel's ability to resist cracking.  It is the very thing that makes 1144 so wonderful to machine (the chips form and break away easily) that are it's curse for use in repetitive firings as a cannon.  It becomes brittle.  Then at some later time as it gets harder, more brittle it breaks all at once.  1018 on the other hand has the resistance to cracking that is ideal for cannons.  Use it.

(Charpy notch test is ONE of the indicators that shows the metal's resistance to cracking.  Compare those numbers.  Using the standard rules of thumb for wall thickness compared to powder chamber inside diamtere will get you the design for adequte thickness.)

[Double D]

In the  link list you will find a link to Antique Ordnance Publishers order their plan package No. 12.

No 12 includes full scale plans for Six Civil War Cannon on a No. 1 Field Carriage, (10 Pdr PARROTT Rifle, 3 Inch Ordnance Rifle, 6 Pdr gun, 12 Pdr Field Howitzer, Rifled 6 Pdr Gun, 3 In PARROTT Rifle) $20 for 120 pages of drawings with postage of up to $14 to west coast.

These are full scale drawings that you would have to scale down for your project..

[Part 77]

I will order the plan to go with the 1018 mild steel.
Wheels? I found some at the link below that seem suitable. They are 12 spoke instead of 14 though.
http://www.amishcountrycreations.com/product/189-18F

I've found other wheels that are more economical but look too "spindly" and narrow. The quest continues. Thanks again!

[Double D]

Again, got to the link list there are numerous wheel makers listed and some offer cannon wheels.

[Part 77]

I have been studying the N-SSA regulations on full size cannon barrels. They require a liner. Is this needed for my project? Please bear with me. I want to be absolutely safe when firing my cannon.
I will be building a 1/3 scale, not 1/4 as I originally planned.  I am using 3 1/4" 1018 bored to 1". This will make the breech wall thickness more than 1 caliber thickness by 1/8". My Antique Ordnance Publishing plans are enroute, so I haven't got actual dimensions of the 3" Ordnance rifle yet. If 3 1/4" diameter of my model is wider than it should be when scaling down the original size, so be it. I would rather have a little extra material. As I said, my model will be "roughly" based on the 3" gun.
Does the breech end of the bore need a special shape/radius or can it be left as drilled (135* drill bit point contour)?

[Double D]

I have been studying the N-SSA regulations on full size cannon barrels. They require a liner. Is this needed for my project? Please bear with me. I want to be absolutely safe when firing my cannon.

To meet N-SSA standard you will need a liner.  But wait.  The numbers used for the liner dimensions are minumum standards. The liner can be greater than those dimensions.   So if your 1018 barrel exceeds the minimum dimensions you are fine.

I will be building a 1/3 scale, not 1/4 as I originally planned.  I am using 3 1/4" 1018 bored to 1". This will make the breech wall thickness more than 1 caliber thickness by 1/8". My Antique Ordnance Publishing plans are enroute, so I haven't got actual dimensions of the 3" Ordnance rifle yet. If 3 1/4" diameter of my model is wider than it should be when scaling down the original size, so be it. I would rather have a little extra material. As I said, my model will be "roughly" based on the 3" gun.

All my guns are roughly built, ask any one who has seen them! 

Does the breech end of the bore need a special shape/radius or can it be left as drilled (135* drill bit point contour)?

The N-SSA rules call for a radius.  The area of concern is the sharp corner transitioning from bore to bottom.

[dan610324]

its always better with a bottom radius, sharp corners are senitive for stress
but if you drill it out slightly undersized first with a standard drill , then you can shape the final size drill with a radius
ok , freehand shaping will not be perfect , but if you really want it perfect you can come very very close if you just do it slowly and checking the result frequently

no your barrel doesnt need a liner , its machined from a solid bar
your barrel will be a giant liner by itself  

[Part 77]

I finely spoke with the man referrenced above who's daughter was injured.
I was mistaken about that injury and the one in which the young boy was killed. They were 2 seperate events. The boy's injury happened in 2007. (according to the man)
The one in which the woman was injured was in 2008. Both in Thurston Co., WA.
The man said that the "cannon" was "...made from a piece of pipe just for that." It had been fired many times that day when he was present. The accident happened later that evening after he had left. Alcohol use was involved. One piece of schrapnel traveled nearly 200 yards and penetrated an exterior wall of a house, lodging in an interior door. The injuries were not only physical, but emotional as well for all present with lots of hard feelings still, among the "friends" involved.
It was nearly 2 hrs. before any one fessed up to the responding EMTs/LEOs that a "cannon" exploded.
When I asked him for specifics of the "cannon's" dimensions/material etc., he was unsure, saying it was a "heavy piece of pipe.", indicating by hand a 2 1/2" OD more or less. He was sure that black powder was used and not smokeless, at least when he was present.

[dan610324]

thanks for that info part 77