All old hearths I have seen in Europe and Scandinavia look more or less like this.

What has always impressed me is that with rather simple tools and a hearth, such impressive objects were produced. However, I wonder if cause of that is in part because there were "finishers" that took objects made by smithys, filed, polished, outfitted, etc. them into final, impressive objects.

At Vira Järnbruk in Sweden, in 1783 a bladesmith was paid 8,5 daler coppercoin per blade for a cavalry rapier, which included smith's cost for raw materials, whereas the finisher received 37 dalar coppercoin per final rapier (handle, handguard, and mounting of them on blade). Would expect something similar for firearms.

Niklas