Hello all, I hail from northern Michigan. I used to shoot ML's in compition with my parent's. That was awhile ago.I'm pushing 40 now and recently cannons have caught my interest and I am thinking of building my own cannon. I don't think I will be shooting in comp's any time soon but who knows.I have alot of ?'s and think the people on this site will be able to answer all of them. So here goes, a golf ball cannon will be my 1st build.
Welcome to the board.
I've fould one that I like it is built by Cannon Thunder- cannonthunder.com they call it the Marcia cannon. I plan to make mine very close to this one.
Interesting looking cannon. Its a conceptual piece not really representing any specific cannon. It is a nice looking piece.
I plan on using 4140 seamless tube and i also want to rifle the barrel for better accuracy 11" bore length.
With a bore that short why not just use a solid piece and just drill and ream? You will then do away with the issue of setting a breech plug in place.
Why would you want to rifle a golf ball cannon there is nothing to be gained. For the size gun you are building, shooting round ball out of the smooth bore with zinc or steel will be plenty of accurate. A golf ball will not.
Bore diameter is my 1st ?. I see you guys talk about windage but with my plan on rifling the barrel I think a patched gb with .005" to .010" windage on the bore would be what I want- 1.685" to 1.695" but I'm sure? Next ? chamber dim's and shape. How big should the chamber be and what shape should it be and what size charge should it hold.
Golf ball bore with proper windage is 1.72. Since you are going find out real fast that golf balls don't fly straight out of cannon bores you are going to be looking for some other solid balls. We have a group buy for steel golf balls listed in the cannon classifieds. Also listed in the cannon classifieds is a group buy for pop can size zinc balls from Rotometals. Rotometals also have golf ball diameter zinc round balls.
You will find it very difficult to chamber and seat a patched round ball of golf ball diameter. Because of the total surface area in contact with the bore it takes great deal of force to seat a ball that large. You will need a big hammer and even then you will find problems.
If you make a straight bore you will need a barrel at minimum 5.16 diameter to meet the safety guidelines we recommend. It's your choice to follow those guidelines or not, and you may be on safe grounds using 4140 and the smaller dimensions. If you make a howitzer chamber you can get away with the smaller diameters you mention. To determine the correct chamber size divide the barrel diameter over the chamber area by 3 and that would be your maximum safe chamber size.
Rifled bores work better with conical projectiles than round ball.
How are you going to rifle the bore? Are you set up to do rifling?
The major od of barrel should be 3.5" to 4.5" to conform with what y'all say is safe. I am a resonably good machinist and good welder but I plan to have all my welding done at a local tank and pressure vessel shop, just to be sure. Any comment from anyone will be helpfull. Thanks to all in advance.
May I suggest you find your self a set of plans for a specific cannon and scale that to golf ball dimensions before freelancing and building the Marcia gun. This will give you a feel for cannon building and make things a bit easier when you take on the Marcia.