Wildeboer, it was an interesting link. Thanks. That build follows the traditional underhammer style with the nipple screwed directly into the barrel and a flat spring trigger guard serving to power a swing hammer. My approach is going to be quite a bit different.

By the way, "holding thumbs" is a new expression to me. Is it a common one in South Africa? I assume it's much like crossing one's fingers for luck.

Bronko, the ramrod will go under the barrel in a traditonal way. It will either be full bore length and protrude 3/8" beyond the muzzle, or align with the muzzle and be 3/8" too short of reaching the face of the breech. I haven't decided which yet, but will probably let it protrude.

The forearm will be attached with screws to two ramrod pipes that are silver soldered directly to the barrel. The crude and not to scale diagram below shows the method. I thought about putting an underrib on the barrel but decided I didn't want one.