Crosman 700 inconsistent velocity

[MachWon]

I was given a Crosman 700 .22 caliber CO2 powered rifle by my childhood best friend. I disassembled, polished, reblued and re-sealed the gun. I put a new hammer, hammer spring, and valve assembly in the gun plus all new seals. Most of the time, I get very low velocities, but every now and then I get full powered shots. Any ideas what might be going on?

Gary

 

[Ascot500]

This is just a swag but, check the tip on the CRS700-015 Hammer
It's a delicate part and if it's broken, the gun will still work but at a lower velocity

 

[MachWon]

I replaced the hammer when I rebuilt the gun. It was indeed broken as you described. The gun shoots at low velocity even with the new hammer.