"Best" lock won't set in locked position [photos]

[h3x1lu2]

I encounter these locks quite frequently, and when you turn the key one way, it unlocks the door (clockwise I believe) and that is a full turn but when you turn counter clock wise it locks the door and that's at only about a half turn, so that would explain the 180 degree turn that doesn't open the door...Best padlocks also do the same but turning it the other direction doesn't do anything...as a general rule of thumb, Best turns clockwise to open counter (in the case of door locks) to lock...also, now I don't know much about core removal keys but perhaps that could also have something to do with the half turn that seems to do nothing...

[dougfarre]

How many pins does this best lock have?

[Varjeal]

After reading through the maze of posts, I think I've figured it out.

The cam on the back of the cylinder that engages the latch is worn and thusly slips past the proper location to move the bolt.

In UK laymans terms, Your lock is stuffed. Use it for picking practice only.