Newb with questions, pic, field cannon.

[Eugene]

Hi all,
 
First post in the Cannon section, love the info and video’s, nothing beats a black powder “boom”.
 
I found some plans, I think it was here or from a link here, I think it is a French field gun, but I am not sure, but it had a nice shape so I made it anyway.
 
Some questions if I may.
 
Where can I find some good pictures or even plans of a field type carriage, scale and authenticity are not too important, I just want it to look “right”.
 
The cannon ended up 17.5” long and 2” max dia, I was thinking 18” to 20” dia wooden 10 or 12 spoke wheels about 1” wide, with the rest of the carriage out of hardwood.
 
I have not put it on the scales yet, but it is heavy, made from 2.25” dia brass bar.
 
Has a .453” dia bore, done this size as the balls for a ruger old army are .451” but doing some reading here it should be closer to .465”, I can fix that before firing though, I will grab a reamer and get to it.
 
The trunions are not fixed in place yet, I was thinking of silver solder, but was worried thet the amount of heat to silver solder, on that size barrel may harm it, would soft solder be strong enough?
 
It is nose heavy, so elevation screws will be required in the carriage, was going to put one in front and behind the trunion centre line to keep control both ways, does this sound fair.
 
The lead balls I plan on using are about 160grain in weight, was thinking of a 25-35 grain charge of FFF as a workable load.
 
It has a wall thickness of .700” at the breach, tapers to a min of .430 at the end of muzzle (not inc the raised fancy bit), the thinnest the wall thickness gets is where the trunions attach, as the trunion mount holes are offset to the top and counter bores with an end mill, the wall thickness at that point is down to .160”
This is approx 5” forward of the breach . the bore is a total depth of 15.375”.
 
How much will this move about under firing, carriage will be of hardwood and steel construction and should weigh 20-30 pounds.
 
Is this a usable and workable item or have I got a shelf sitter?
 
Thanks in advance.
 
PS, forgot to add, in the photo, it is laying next to an 18" long shifter so you get an idea of size.
 
 
[IMG]http://media.use.com/images/s_1
 

[GGaskill]

The trunions are not fixed in place yet, I was thinking of silver solder, but was worried that the amount of heat to silver solder, on that size barrel may harm it, would soft solder be strong enough?

Silver solder would have great strength but the heat required to melt it will completely anneal the barrel for a good length.  I would not recommend that.  In fact, the attaching of trunnions issue is a good reason not to fabricate brass barrels (versus casting them) because a strong joint is difficult to achieve without damaging the barrel.  You could try the mostly tin silver solders sold today for lead-free plumbing work.  They are stronger than tin/lead solders and melt more easily than true silver solders.  Keep the heat to a minimum.


 
It is nose heavy, so elevation screws will be required in the carriage, was going to put one in front and behind the trunion centre line to keep control both ways, does this sound fair.

Your barrel is extremely long compared with most real barrels.  If you are free to consider shortening it, that would help with your balance problem.

[Double D]

It is nose heavy because the Trunnion is to far to the rear.  Can you move the tunnion forward.

The SAMCC Club cannon that I used when I was lived in Durban had trunnions pressed on a steel pin that ran through the bottom of the barrel.

[Eugene]

It is nose heavy because the Trunnion is to far to the rear.  Can you move the tunnion forward.

The SAMCC Club cannon that I used when I was lived in Durban had trunnions pressed on a steel pin that ran through the bottom of the barrel.

Hi again,
 
Moving the trunion is not an option as the holes are bored for thier mounting, I think I will however dock the barrel back to just infront of the second ring, removing about 3" in length, that should even things up along with get it better proportions, I just used the print supplied and scalled up till I had 2" od to suit the bar I had, not giving too much thought to overall length.
 
If it is still to nose heavy after the docking, I could add a discrete weight under the rear if required.
 
Do you think it will handle the 160GR lead ball and 35Gr of FFF or do I have a bomb?
 
Thanks for the replies.

[GGaskill]

With a wall thickness of .700" and a bore of .465", you should be OK.

[Double D]

Here is the load chart for smooth bore round balls from GOEX.  http://www.goexpowder.com/images/LoadCharts/RB-Rifle-Musket.pdf

I would treat these as heavy loads in a cannon.

[Eugene]

Hi again,
 
I have attached the trunnions to the cannon, used a high tin soft solder, tinned the holt and trunion, went really well, nice and tidy, minimal heat into the cannon as a propane flame was used with slow heating, I tried to rip one out after it cooled, held it in vice, twisted and pulled as hard as my 250lb body would allow, no movement, just a galled up trunion, but easy fixed.
 
I also did a couple of test runs with powder and wadding only, wads from heavy cloth rolled and stuffed into bore after 20gr of black powder (geox FFF), really nice BOOM, I think the long barrel? or bore? helps give it a big deep boom, nice long flame too, shook dust from the rafters.
 
I would like to get a load sequence to suit this if I could, I have a few questions regarding this, I will be using the following components.
 
Geox FFF powder
140gr lead round ball .451 in dia
.125" cannon fuse, the green chinesse stuff.
 
Do I patch the ball like a musket, I know they do it to engage the rifleing, but what about cannons?
 
Should I run a wad between ball and powder, if so, what sort, lubed or dry etc.
 
Sorry for so many questions, but I just dont want any mistakes here, too much at stake.
 
Thanks again.

[RocklockI]

I like the way you tested the solder job , galled trunions suck but are better than some 'issue' down the line .
 
I can't hardly imagine what that 'issue' would be with a heavy 17" barrel and a .45 cal ball but ...
 
No patch no wadding just powder and ball . What would you do if a ball with a patch got stuck 1/3 of the way down ?
 
With those dims and looks it reminds me of a Culvern ,Demi Culvern , Saker, ect.
Good luck
Gary
 
 
 
 

[Eugene]

I like the way you tested the solder job , galled trunions suck but are better than some 'issue' down the line .
 
I can't hardly imagine what that 'issue' would be with a heavy 17" barrel and a .45 cal ball but ...
 
No patch no wadding just powder and ball . What would you do if a ball with a patch got stuck 1/3 of the way down ?
 
With those dims and looks it reminds me of a Culvern ,Demi Culvern , Saker, ect.
Good luck
Gary

Thanks for the info,


I figured if the trunion didnt come out with 250 lb and 6ft of me twisting, pulling and generaly beating it up, it wont come out under recoil of 30gr of fff and a45 round ball.


I have cleaned the trunion up with a smooth file and emery tape, cant see it now, so all is good. looking forward to a test fire on Friday.