Technology is all over the place. We think of modern guns that are over 100 years old in design, ie Colt 1911.
Shotguns were typically hammer guns for reason of simplicity and effectiveness in function. I have a George Daw side by side that looks almost new as it's condition is so exceptional. It is over 150 years old. It was made in 1867 and shoots 12 gauge 2 1/2 inch shells. Many think that is normal, but you have to remember that in 1867, the main type of firearm was still percussion.
This gun is one of the earliest guns to utilize the center fire cartridge with outside priming. Again, we think nothing of this today as we have been using this type of priming all our lives, but this was revolutionary. George Daw also owned the patent on center fire priming and had gone through a few lawsuits to protect it.
This gun is not only a beautiful piece but historic in it's place in firearm development. I still use it in Cowboy Action shooting and chasing birds around in the fall...