Birmingham has always had an adequate supply of craftsmen able to finish guns to best work standards, both in-workers and out-workers. Keep in mind that there are many routes to get from forgings and blanks to finished gun; rough forging, machined forging, rough finished forging, barreled action, gun in-the-white, finished gun. The trade used all routes as far as I can tell at one time or another.

In the case of H&H, they seem to have gone from bought-in guns to their own complete factory. There was most likely a considerable series of steps from bought-in to factory. Older small shops seem to have gone from bench made guns to buying in at some level. Younger shops seem to have started at a more nearly finished to finished gun. Vendor shops seem to have usually had a service shop. Depending on work load and skill of on-the-books help, they likely bought in guns at some level of completion to provide for slack time work. Out-workers were available to do any work the shop was incapable of doing on its own. Very few, if any, of the brands have done it one way exclusively.