This fascinating Youtube video appears to be a condensed edit of a longer documentary or promotional video about legendary gun maker Holland & Holland. It shows the guns being made, tested, sighted and regulated. Regulation refers to the barrel alignment process. Both barrels of a double barrel rifle should impact at the same point. The image above shows two barrels being re-soldered together after an adjustment to their alignment.

Read about Miles Vining’s visit to the H&H flagship store last year.

Many thanks to Jay for the tip.