What have you tried so far?
The first few things that spring to mind are:
1) Is there much air in your tank? once a HPA tank gets to about 1,000psi it starts to spit them out
2) Have you adjusted both the Regulator and LPR Regulator with an allen key so they let more air through (Righty Tighty Lefty Loosey)
3) Tried putting in a fresh battery?
4) Have you looked at cleaning out the Regulators? If there is loads of dirt and filth in there then it can affect performance (Note, be careful with the washers when taking apart the inline regulator, as they need to go in a specific patterned order (See manual on how to dismantle and rearrange them)
5) Also check to see if the rammer and bolt are properly oiled up and fitted with the correct Orings, if these arn't done then it can cause more friction and potentially cause the rammer to get stuck