sorry you're having problems with the 600. I bought this gun back in early february and for various reasons did not actually receive it until late march. when i got it i immediately loaded it and started shooting with the cartdige that was in the gun. it was shipped charged and held its charge all that time. since having it i must have loaded 7-10 cartridges with no problem, and sold it in good faith. no mod was done on this gun. the mod i posted was in response to a question someone posted as to whether it had a piercing cap, and what i posted described a procedure published by Crosman for modifying it so it would take a standard 160 piercing cap. maybe a seal or something just had its last hurrah when i shipped it to you. if you wish to return it to me or have me pay for its repair, pls. email me and we can discuss.
again, sorry for the problem you are having. I know it really sucks when you wait for something and then when you get it doesn't live up to expectations.
