Help with cannon balistics please

[CANNONMAN]

I will be taking several cannons out to chronograph them. Anyone know if there are numbers I should be seeing? Too slow, too fast, just right? They are: 5.5' X 2.8" - 3#, 3'X 1.74" - 1.7#, 4'X 1.75" and 12"X2" - 2#. That's length, bore and ball mass. I'm shooting homemade BP so I don't have a "known" power source. My stuff probably has a bit more kick than Goex cannon. 6oz, 3.5oz, 3oz and 2.5oz are the powder charges. Everything shoots 500yds with ease. Just don't want to walk much farther. Anyway, any thoughts on how fast and far these should be shooting would be great. As always, thanks all!

 

[ofitg]

Found an online ballistics table for Civil War cannons -

http://civilwarwiki.net/wiki/Principal_Characteristics_of_Common_Field_Artillery_Pieces

With regard to your first three guns - 2.8", and 1.75" bores - I would note that your powder charges (relative to projectile weights) are on the "light" side, compared to the Civil War guns. On the other hand, your barrel lengths (relative to bore diameters) are considerably greater than the CW guns.
If your projectiles fit properly in the bores, and if your homemade powder is up to snuff, I'm guessing that you might exceed 1000 fps.

With regard to your 4th gun - the 2" bore in a 12" barrel - I can only guess "less than 1000 fps".

I'd be interested in hearing how that small-arms chronograph works out with such large projectiles!

 

[CANNONMAN]

Thanks! It's kind of spooky to advance the charge. I know the specs on the cannons support the pressures but it is still a mighty boom! I should have some data this March.