Forgive the newbie question- Muzzle plugs?

[jamesbeat]

This must be one of the things every experienced cannon enthusiast knows the answer to, but doesn't get talked about much.
I have seen a few cannon in real life, and many in photos, which had a wooden, well I guess you'd call it a 'plug', stuck into the muzzle.
I presume that these are to prevent debris getting into the barrel, but I don't know if they are historically accurate, or something that places that display historical cannon do to prevent people from dropping coke cans down the bore.

My best guess is that they are a device that was used when the cannon were being stored/transported to keep debris and rain etc from entering the bore, but I'd like to be educated a bit more about them, including what they're actually called!

Does anyone actually use these on their replica cannon?
How long is the part that goes into the bore?

[KABAR2]

They are called Tompions most were made of hardwood some were a little fancy with brass caps, there was one on auction not long ago that had a fancy cast iron face with knob and a wood insert for the muzzle. tompions were not only used on cannon they also made them for muskets and rifles right up through the civil war to keep the rain out.

[Zulu]

Here is one I made for a Verbruggen barrel.
Zulu
 

[jamesbeat]

<a href="//" target="_blank" class="new_win">//</a>KABAR2, thanks for the info, I didn't know they were also used for muskets, but it makes a lot of sense as muzzle up carry is asking for rain in the barrel!

Zulu, that is a fine piece of work, I wasn't aware that they had leather straps to secure them, bit again it makes sense.

Would these have been used during lulls in battle when it was raining, or would it have been more of a storage/transport type item?

[Zulu]

No matter what is going on, a wet load is no good.  Use them when you need to.
Zulu

[Zulu]

Here is another one I made for a 3" bore Parrott rifle.  Also seen is a vent plug.  It is a copper plug that goes in the vent and prevents water from entering.
Zulu
 

[KABAR2]

Here is one that has a cast iron cap that was at auction not long ago.... not sure as to era...

[jamesbeat]

Zulu, you have some nice tackle there!

KABAR2, that cast iron piece is nice, thanks for digging up the photo. It reminds me of the lid of a jar my mom used to have when I was a kid
I haven't thought about that jar for around 30 years, but the memory instantly popped into my head when I saw that photo.
Weird that it was stored somewhere in my brain for all that time...