I was recently able to get ahold of a loose Sargent 8200 cylinder and after a difficult 22 minutes later was able to get it open. This one was 6 pins. I also looked on Sargent's website and saw two other higher security locks on there (not sure if the cylinders were different or not). I would be interested in finding out more about particular locks and how they are constructed but when looking at the websites of the companies they basically only have instructions on how to install them. I was able to find that this was a grade one security lock, which is supposed to be good according to another site I found.
I used a regular pickset in order to do this with a quick taping mixed with pushing technique. I would have looked more at the structure of the lock but it had a hard casing and it wasn't mine to try to take apart. Is there anyway I can find out more about high security locks according to individual models? I've heard of some top pins that are designed to get caught in the shear line when tension is applied before the pins are set and was wondering if this lock had that. Maybe that's why it was such a pain. Also, I apologize if this lock didn't belong in this forum.