My grandfather carried an Iver Johnson break top revolver in the Alaskan Gold Rush.
I started buying them at gun shows 10 years ago at $50 for working and $35 for broken.
The most common failure is the trigger spring.
I have fixed a lot of them.
Prices have gone up.
It is now $50 for broken and $100 for working break tops.
I overloaded a 38 S&W with a 38 Super +P load and the latch got loose.
I said to my father, chief engineer over 150 engineers in a gun and vehicle design company, "I had too much pressure."
He snapped at me, "That is not from pressure! That if from recoil pulling on the barrel mass and from bullet friction!!"
It took me a while to understand that, but now I do. I only shoot soft lead bullets in break top Iver Johnsons.
The 38sw latch is a tiny piece of sheet metal with a hole in it, and pinned with a #5-56 screw, or something odd like that. The latch stretch and makes the action loose by making the hole in the sheet metal oblong.
The 32sw latch is even smaller, #8-64 screw or something odd like that.
The 32acp jacketed ammo [it is actually semi rimmed] will drop in and fire in a 32S&W, but just one shot can stretch the latch.
There are many variations in the Goforth book, and the later revolvers seem to have a tougher latch.
These days I typically put one grain of Unique or Bullseye in a 32sw with a soft lead bullet. That can be a lead ball.