Can't get co2 to pierce on crosman

[Ferrets Bueller]

Bought this pistol the other day and its just arrived, can't get the co2 to pierce all it's doing is leaving a small dimple in the end if the co2 cap. I've owned loads of co2 pistols including a 2240 so I know how to load them am I missing something as its got a 2250 cylinder on it. I'm guessing the piercing pin is worn?

http://www.airgunbbs.com/showthread....d-Crosman-2240

Just took this pic of the co2 piercer looks as though it's hardly protruding at all and the brass around the edge is damaged too.

http://i181.photobucket.com/albums/x...s/6c4aeb47.jpg