[Old School Punk]

Hey guys; Would someone out there care to give me/us a quick overview of the reasons for installing shims in airsoft mech box.

Is the idea to get rid of play between the gears, or is it to space the gears out , or is there another reason?

I suspect this has been discussed before, but if you would be so kind as to review it one more time, it would be much appreciated.


Thanks in advance

Gordo