Here are a couple of orginals. The big one is an Austrian tube lock which is uncommon in original form as most were converted to percussion cap. It is big and measures about 17.25" overall and has a bore of about .70 cal. I had meant to take a picture of the both of them together so you could see how large the Austrian pistol really is. The other is a US 1842 by H. Aston in .54 cal smoothbore and is only about 14.25" overall.