How to tell if I have a gas spring

[Bubbacop]

Hi 
i bought a used British webley stingray in .25 caliber years ago. The former owner told me it had some kind of gas ram instead of a spring
My question is how do you really tell that it has a gas spring .
when I shoot it it doesn't have that twang that a spring gun has and cocking the gun is very smooth and easy it compares to my Beeman X2 which I know is a gas ram. 
The other question is, I chronographed the rifle and it's shooting in the 470 fps range with 26gr pellets that was the lightest .25 cal pellets I had and it seems somewhat slow to me if the rifle is a gas ram can I raise the power somehow 
i haven't been able to find much info on the UK made stingray.

Thank you in advance 
sergio in Miami

 

[LE_gend06]

Open it up and check out the insides. Find a forumer familiar with the model and get some help if you aren't sure how to go about doing it. 

Or check out some YouTube videos you can find some instructions. A spring gun has a spring hence the name. Gas Rams have a piston. 

Do some research online for your model and maybe you will find if its solely a springer or gas ram option