Can a Gamo Whisper gas ram be improved when under powered

[MarkHolding]

I have a Gamo Whisper IGT and it is shooting at an average energy of 9.4 ft/lbs. It has been like this since new about eight months ago. Will shimming the gas ram, as with a normal springs add extra power, or does the gas ram pressure remain constant even if shimmed. I have been told that the HW90 could be adjusted by a valve at the rear of the ram and a special pump. I haven't had the rifle apart yet, but wondered if anyone had fine tuned their gas ram. My goal would be 11 ft/lbs, so not much extra energy required, possibly 50 or 60 feet per second. As it is still less than a years old, hopefully it can be sent back for adjustment. There isn't much information on this subject out there. Has anyone had this experience?

[bighit]

your ram will be a sealed unit unlike the HW90 one.

your ram here http://www.airgunspares.com/store/pr...r-IGT-Gas-Ram/

HW90 ram http://radecek.fm.interia.pl/gasram.jpg

if still under warranty and not messed about with, take it back to the shop you bought it from.