the carriage is based on "British Smoothbore Artilery 1650 - 1850" which covers virtually everything you might want to know about all types of cannon.
On a practical side, I started with the wheels at 9 1/2" diameter because anything much smaller would be just too awkward to make. I then scaled the length of the trail (carriage) to the diameter of the wheels. The cheek pieces were sort of based on that scale. Some dimensions are approximate for a variety of reasons but overall the idea was to try and have everything look appropriate to an original. I also however left off some small details because they did not scale down well and/or would be too flimsy on a gun that will fire blanks occasionally.
The first big decision was the ration of barrel to carriage; the British seem to have sort of had one size of carriage for many barrels although these carriages varied in width because of various barrel widths and must have varied in the position of the elevator based on barrel length. I plan to use the same size carriage for a howitzer barrel and it is about 1/2 the length of the cannon. The elevator screw handle should be mounted on the carriage but in a working model, that is impractical.
Barrels appear to vary considerably in thickness and taper and while I would have liked to make this one with a thicker breach, but I chose to make it from phosphor bronze tubing of 2" OD and .9" ID. Essentially you can have a moderate range of tapers and simply call the gun a 10lber instead of a 25 lber. Trunions are silver soldered on after turning the barrel and the barrel must be well supported to prevent sagging because the flow temperature for the solder is only about 300 F below the melting temp of brass. I soft soldered the trunions to bar stock then turned the ends to a tapered concave shape to match the barrel.
Hope this is of some use.
cheers mooncoon
