cannon safety

[Robyn]

hi
I have been reading this forum with great interest on cannon safety... While I fully agree that a cannon should only be constructed from the correct and certified materials.. and a design that is proven to be safe There is one point that you all appear is have missed. The short start load... now before you all poo har me it is quite possible to short start a cannon load. and just like a musket the result can be BOOM! cannon reduced to scrap metal and possibly personal damage.. this is fact and regardless of the quality of the cannon it can and does happen.. So while all advice about the construction of cannon is good to have it is only as good as the person loading the finished product.. Maybe before newcomers start playing with cannon construction they do a bit of study on how they work and what makes them go BOOM!... I hope this serves as a timely reminder that we are not playing with toys, Cannon were made to kill and they don't care who...
Regards Robyn

 

[TheDoubleD]

Humor me, whats a short start load?

 

[Robyn]

basically a short start load is when the projectile is not placed on the powder charge, meaning there is an air gap in the chamber... between the powder and the shell this causes a rise in the chamber pressure as the shell becomes a blockage in the barrel and kaboom! the barrel can burst..

 

[TheDoubleD]

If you have properly marked your rod for the depth of the powder cartridge and the depth of seated ball and you have proper windage this is not a an issue in cannons.

 

[Rob Dinwiddie]

It usually only becomes a problem when a cannon is depressed for direct fire and the projectile tries to roll out of the muzzle. This is why many of us patch cannon balls. It's a bit safer than an overball wad, protects the tube from projectile wear and prevents forward roll even when the muzzle depression is excessive. Of course in a rifled gun a cylindrical shell such as a hotchkiss or an ordinance rifle shell can't roll forward.

Capn'D

 

[TheDoubleD]

Actually to address the issue of the the ball rolling out when the the barrel was depressed a sabot was used...

 

[Rob Dinwiddie]

Yes you're certainly correct. I've used and made them but in the early and mid 18th century they were uncommon so most of the shooters with my group have rarely seen one. I wonder if they were used much on board ship. Ships roll and cause unexpected and unwanted muzzle depression. Also all ship to ship fire as well as most pre-1840's cannon fire was direct fire so the muzzles were rarely pointed up at all. I've never seen a round shot rack with provisions for sabot rounds. I guess you couldn't heat round balls after they were strapped to the shoe so until the era of explosive (post 1790's) cannon balls even coastal defense artillery rarely used sabot rounds.

Certainly they would solve the problem today for shooters as long as contact between the tube and iron strapping was minimized. Lots o' Windage

Capn'D

 

[bingo1952]

To keep round shot from rolling forward of the powder charge naval gunners used a grommet that looked like a big o-ring made from rope.