Quote Originally Posted by tacfoley View Post
The 21 is not the bore, it is number of lead balls of the same diameter as the bore that weigh one pound. Your 21 bore musket works out at .60cal. It is therefore not a converted Brown Bess - that's .69cal.

Can you post images of the lock, please?
ahhh ok I get it now. I do have images of the lock but it was way back and they are not good quality, ill send a link anyway but I am there again on Wednesday so ill get some better pictures then.

Also what nipple thread are these? or does it vary between guns?

Here are the images of the lock, like I said, it is pretty dark and not the best images but i will get more:

https://i.imgur.com/gSBYxZo.jpg

https://i.imgur.com/vvfUcoA.jpg

https://i.imgur.com/DICYGOR.jpg

Also as a bonus, here it is on my grandfather wall along with two shotguns:

https://i.imgur.com/Prl4mrs.jpg