Ball diameter

[pfw4666]

I have a cannon with a .750 bore.  I am thinking of shooting round balls out of it and I was wondering what Lyman mold I should get.  Should I get the .715 or the .735 diameter mold?  Also, which patches will I need and where can I find them. 
 
Thanks in advance,
 
Paul

[GGaskill]

Normally you don't use patches in smooth bore cannon so I would get the .735" mould.

[ironball]

Either one will work. Thicker patch for smaller ball, thinner one for bigger ball. The bigger ball loaded naked with a wad under it is good. It's not really a cannon, and can be loaded just like a shotgun.

[pfw4666]

What type of wad do I use?

[Cat Whisperer]

I have a cannon with a .750 bore.  I am thinking of shooting round balls out of it and I was wondering what Lyman mold I should get.  Should I get the .715 or the .735 diameter mold?  Also, which patches will I need and where can I find them. 
 
Thanks in advance,
 
Paul

You've not described your cannon's construction.  Smoothbore shotguns/muskets have VERY smooth bores and typically are engineered well.

I'll not ASSUME that about a cannon; to do so may get you killed.

Cannons run the gammit.

Patching will increase pressure.

The larger the bore the greater the area upon which that pressure pushes.

Larger bores accomodate this by using windage (clearance) to control the peak pressures.

Having said that, have you checked for the recommended load from the manufacturer?

Typical rule of thumb for windage is to subtract 1/40th of the diameter of the bore to get the diameter for the projectile.

That gives you about 0.732" diameter unpatched. (0.01825" clearance)

[pfw4666]

I apologize for not describing my cannon.  It is a 1/4 scale 1841 replica.  The entire cannon is 18 inches long.  It is newly manufactured out of steel (I am not sure of the alloy). 
 
The guy I bought it from said that I could shoot anything I wanted to out of it.  He did give me a couple of charges to try.  I measured them out and one was 360 grains and the other was 420 grains.  Both loads are FFF BP.  These loads are just for noise and smoke.  I am going to see this guy next weekend and have several questions for him.
 
I have experience with  BP, but no experience with cannons which is why I joined GBO.

[muskeg stomper]

I'm new to cannons myself but have shoot muzzleloaders for years. Your charges sound VERY excessive! Take a look at the "Safe Loads and Construction" stickey at the top section of this forum.

[ironball]

They are probably OK for blank loads. Most of that powder is wasted, it just gets blown out the barrel to burn in the atmosphere. Not very much pressure if not tightly wadded. I woudn't try them with a ball, though. Ouch!

[Cat Whisperer]

I'm new to cannons myself but have shoot muzzleloaders for years. Your charges sound VERY excessive! Take a look at the "Safe Loads and Construction" stickey at the top section of this forum.

http://www.gboreloaded.com/forums/index.php/topic,89682.0.html

For 3/4" bore the chart (for under 2") reads 100gr.  (for unpatched ball attached to sabot)
Typical blank charges are 2x that charge.

FFg will give you lower peak pressure for same charge, and as it burns slower will work as well.

[Cat Whisperer]

I apologize for not describing my cannon.  It is a 1/4 scale 1841 replica.  The entire cannon is 18 inches long.  It is newly manufactured out of steel (I am not sure of the alloy). 
 
The guy I bought it from said that I could shoot anything I wanted to out of it.  He did give me a couple of charges to try.  I measured them out and one was 360 grains and the other was 420 grains.  Both loads are FFF BP.  These loads are just for noise and smoke.  I am going to see this guy next weekend and have several questions for him.
 
I have experience with  BP, but no experience with cannons which is why I joined GBO.

I'd begin with 100 gr of FFg and work up to maybe 200gr.

Blanks DO produce high pressures - you become a believer of it within milliseconds of seeing a cannon firing blanks explode.