Cannon cast pb/rifling twist?

[Olevern]

I am contemplating making up a replica of the 1.5" Hughes Breechloading civil war cannon. I have contacted someone to give me a quote on making one or more barrels and am having difficulty finding solid info on the piece, particularly specifications. There were approximately 12 pieces put into use in Confederate units, only one known to survive. It is currently for sale on Gunbroker for $69,000.00, not a bad price for a unique piece of civil war artillery. I contacted the owner/seller via Gunbroker and inquired as to whether he would be able to help me in my project by providing specifications/measurments from his original cannon. He responded that he had some documentation that went with the cannon, but the documentation was part and parcel of the cannon sale, so: buy the cannon and get the documentation. So, dead end there, don't have a spare 70 grand lying around.

Someone has already made a replica, however, after contact with that individual he is no longer in possession of the piece and has lost the notes he made when he measured the original.

Question #1: with a 1.5" diameter, how long should the projectile be to maintain a reasonable dia./length ratio? Thinking of a round nose/flat point boolit, approx. two and a half diameters long.

Question #2: Who might be able to handle making a mold of this size?

Question #3: What rifling twist would stabilize this boolit (and related; what speed to shoot for) most civil war artillery shot at anywhere from 1,200 to 1,500 fps.

Question #4: How deep should the rifling be?

My next step is to try to locate the patent information. Research indicates that Mr. Hughes patented the breechloading mechanism with the confederate states govt. in 1861, then later after the war, filed the same patent with the U.S. govt. patent office.

Any help with any of the above would be appreciated.

Olevern

[The Double D]

Have you posted your request on the N-SSA board http://n-ssa.org/phpBB3/ Better place than here to post...now when I think about it that might not be true, I have always been amazed about the information that pops up here

[HangFireW8]

http://www.google.com/patents

Hughes Breechloading

Is it this one? It says Cochran at the top but two Hughes names at the bottom. Date is 1859, about right.

http://www.google.com/patents?id=-z1jAAAAEBAJ&zoom=4&pg=PA1#v=onepage&q&f=false

It occurs to me... a breech loading cannon may not enjoy the freedoms of ownership that its muzzleloading brethren do.

[MtGun44]

Is this legal? I thought that anything over .50 cal was a destructive device and banned or
severely restricted.

Bill

[Olevern]

Hang Fire,
Thanks for the response, the link is not the one I'm looking for. My research indicates that the "American Machinist" ran an article in collaberation with D.W. Hughes in which the Confederate patents were printed. That article was in the Sept. 5, 1905 issue of The American Machinist , so I would love to find a copy of this magizine.

As for the legality of said reproduction, Fed. law treats firearms of all types (ordanance included) made before 1898 (and their reproductions) as non firearms. State law might apply, so your mileage might vary depending on what state you live in.

[Olevern]

Where are all the boolit designers?

[MtGun44]

"Fed. law treats firearms of all types (ordanance included) made before 1898 (and their reproductions) as non firearms."

Something doesn't sound right. Why are 1892 Winchesters, 1873 Colt SAA's required to
be sold via a FFL if they are "non-firearms"? There has to be more to this, like maybe
if you make it for personal use and never sell it.

Bill

[44man]

"Fed. law treats firearms of all types (ordanance included) made before 1898 (and their reproductions) as non firearms."

Something doesn't sound right. Why are 1892 Winchesters, 1873 Colt SAA's required to
be sold via a FFL if they are "non-firearms"? There has to be more to this, like maybe
if you make it for personal use and never sell it.

Bill
Originals are not treated the same as reproductions.
BP guns are not treated the same either.

[Olevern]

This topic has gotten far afield of the original questions. I assure all and sundry that, prior to proceeding, I will contact BATF and get a response in writing regarding what hoops, if any, I must jump through to go ahead. I am reasonably confident that this can be done, as a reproduction of this gun has been made in the past and fired in competition in civil war reinactments.

[turbo1889]

. . . Question #1: with a 1.5" diameter, how long should the projectile be to maintain a reasonable dia./length ratio? Thinking of a round nose/flat point boolit, approx. two and a half diameters long.

Question #2: Who might be able to handle making a mold of this size?

Question #3: What rifling twist would stabilize this boolit (and related; what speed to shoot for) most civil war artillery shot at anywhere from 1,200 to 1,500 fps.

Question #4: How deep should the rifling be? . . .

Well here is my best stab:


A1 ~ It is my understanding that most non-round-ball early artillery used shells with a 2:1 length to diameter ratio with a pointed tangential arc nose making up the first half of the boolit with the tangential nose curve radius equal to the diameter:

http://farm6.static.flickr.com/5179/5535615205_10376e4be3.jpg (http://www.flickr.com/photos/54455625@N04/5535615205/)

What you suggest sounds a little longer and a little flatter nosed then the original, not that that would be a bad thing if it improves the performance, but if it were me any deviation from normal has to be justified as an improvement and not just a change for change sake. I think I would keep the 2:1 length to diameter ratio and make a mold with interchangeable nose sections with everything from nearly a full wad-cutter to nearly as pointed as the original standard design.

A2 ~ Your not going to be looking for a mold maker per-say you want a custom machinist and a good one. There are several on this forum. Provided you don’t need a hollow base for bore sealing purposes (It is a breach loader right?) then a base pore three piece mold is what I would want. A mounted mold bottom that forms the nose (as I said several different ones for different nose shapes) and then a conventional two piece style mold that slips on top probably a row of four pins sticking up from the mounted bottom in the four corners and then two holes in the bottom of each side of the mold blocks so the top section that forms the lube grooves and body bands part slips on top and the pins on the bottom also keep the top halves locked closed so that you have both hands free for doing the poring.

A3 ~ I would figure the twist via the velocity corrected Greenhill formula using your low end (1,200fps) number and whatever length you decide on. What you are contemplating is much closer to the original purpose and development of the Greenhill formula then normal boolits in normal guns. Since your going to use a cast lead boolit there is no need for a density correction (if you were going to cast with something else like a zamac alloy there would be):

http://farm6.static.flickr.com/5297/5527782040_f62a923395_z.jpg (http://www.flickr.com/photos/54455625@N04/5527782040/)

That would be a twist of 1 twist in 91” for a 3” long projectile (2:1) or a twist of 1 twist in 73” for a 3-3/4” long projectile (2.5:1).

A4 ~ You have me on this one but if it were my project and my barrel cutter wanted a decision from me and wanted it now and I had to just go with my instincts - well I like deep aggressive Newton type wide groove narrow land ratchet rifling so I think I would go for a the major groove diameter at 1.500” and the minor bore diameter at 1.400 with twelve grooves/lands in that style of rifling profile.

[Mumblypeg]

Or you might try mail@artillerymanmagazine.com . The people that do Artilleryman magazine are into all this stuff or know someone that most likely does. I'm sure someone out there knows about this gun.

[Longwood]

I made a 1" cannon about 40 years ago and just for giggles, made a mold for it that had grease grooves. I made the mold as a straight mold but with a insert that was made by machining two identical rings to form the grease grooves that would just slip into a recess machined into the mold. I then milled the two rings down till the two would fit together to form a perfect circle and slip down into the mold. I then cast a bullet and after poking it out of the mold, along with the two piece ring, I would part the two piece rings that made the grease grooves away from the projectile.
BTW, I made the mold itself out of a piece of carbon and did not use a sprue plate. I simply machined off the base in the lathe.

[Olevern]

Thanks for the opinions/info. It was very helpful. I think I now have enough info to relay to the barrelmaker. Next step is a letter to BATF.