The easiest way to learn how to feel what the pins a lock are doing when you are trying to bypass the lock is to actually see what they are doing as you manipulate it. That is the principle behind the visible practice locks that ITS Tactical recently added to their store.
The lock is encased in clear plastic to allow to actually see how the lock works and how the pick manipulates the pins. They have two models – a tubular lock and a pin and tumbler lock. Each of the two models is available with either standard or spool pins.
These look like a tremendous teaching aid. Check out ITSTactical.com.