heroshark

can also be a barrel issue . Either dirt or damage in the bore or crown. Can also be some thing fowling the exit, flash hider, suppressor or catching the outer barrel if poorly centered in the outer barrel. What's the gun?

Sorry yes, as above, I used to use propane in my sig and then hicapa for many years till the price went up. Rarely added any lube and my mags never leaked. I always left gas in the mags often full and still do. Now I run the gunfire smart gas. Most conventional airsoft gasses contain more than enough lube to do the job of maintaining seals, some too much. Your best applying to the needed areas with the thick silicone oil or ptfe grease to keep your seals good.

I wouldn't use it at all and certainly not fire it through my gun.