This is only a "related" answer but the late DeWitt Bailey related to me that during the Seven Years War (what Americans refer to the as the F&I War) the British Ordnance suffered a severe shortage of long land pattern muskets. To deal this they brought in outworkers, mostly cabinet makers and the like to do the stocking. It must be remembered that the listed "makers" nearly always had helpers who are not mentioned in the records but, even with that, they averaged stocking 2-1/2 muskets per day. I think we largely underestimate how much a skilled person equipped with a variety of specialized tools and making a relatively uniform product could do. Now, those stockers weren't making any of the parts aside from the stock but that could also be said for the vast majority of American gunmakers...they weren't making locks, nor in many cases were they making barrels despite what is generally thought. All of those things were the products of specialized makers. Very few, if any, were making the mounts, except, perhaps in very remote areas so what they were doing was largely what those British stockers were doing, assembling the parts into a finished product.
I'm not suggesting they could make a rifle per day...but I am suggesting that the process was probably much faster than we think when we base our estimates on how long it takes a modern maker, who is essentially an artist, to assemble a gun. 18th and early 19th century gunmakers were often artistic but they were, essentially, skilled tradesmen whose livelihood depended on producing as many products as they could.
