Almost certainly the greatest of all the great designs by the great Rudy Merz of Crosman. I had the opportunity of talking to Rudy's son and he told the story of how one day he was playing his accordion on the porch with his dad watching the mechanism and it was from one of the actions of the accordion that Rudy got the idea of the swing arm mechanism in the Crosman 600.

Everything about the 600 including every service manual, every owner's manual, every service station bulletin, recall notice, every piece of paper that Crosman ever published on the model 600.

http://www.amazon.co.uk/Crosman-Arms...dp/1517270766/

Note: still have not been able to kill the Kindle edition. It's not good enough quality to read all of the graphics. Don't buy it.