As you may know, Darra Adam Khel is a town in Pakistan which is famous for its indigenous firearms manufacturing. Many people living in this area are busy making guns and loading ammunition. There are some rough firearm clones made in Darra Adam Khel, but there are also really impressive ones both in terms of design and execution. Sometimes it is really unbelievable how these people manage to make firearms using only basic tools.
The top image of this article shows a local gunsmith operating a barrel rifling device. Although it is not confirmed, some sources say the picture is taken in 1902.
Note the barrel secured in the lower portion of the device and the gunsmith holding the handles of the cutting tool. The cutting tool itself has a spirally shaped shaft, which I assume runs on a guide pin so that when worked back and forth the cutting tool will do a spiral motion thus cutting the rifling at a certain twist rate.
What is even more interesting is that there are newer images from Darra Adam Khel showing an exactly identical device. So even if it is a homemade rifling tool, it should be working great to be used until modern days.