SPEED Airsoft are making HPA conversion kits for sniper rifles:
SPEED Airsoft To Release HPA Conversion Kits for Sniper Rifles
SPEED Airsoft will be releasing soon a full line of HPA Conversion Kits for the popular spring power bolt action airsoft rifles. These will include the Echo1 M28, Echo 1 ASR, VSR10, L96, APS-2 platform of snipers (Classic Army M24, UTG and Maruzen), as well as the Ares MS700.
SPEED HPA Conversion Kit works perfectly with any stock trigger group and will enable any of the above sniper rifles to achieve a velocity speed from 350fps up to and over 500fps. Cocking the bolt will be much shorter than a stock set up and can even be done with one finger.
SPEED HPA Conversion Kit will require a compressed air tank along with a HPA regulator. The air tank can be as small as a compact 13ci tank, which can yield up to 500+ shots depending on the velocity setting.
For more info, visit SPEED Airsoft at www.SpeedAirsoft.com or get your SPEED products from SPEED authorized airsoft dealers worldwide.