Be careful not to take their tests to say your gun won't work well on 0.30gs bbs. You should try to chrono with them and see if your hop is robbing much joule wise as .30s are great if you can hop them. Theres also talk in other threads of cylinders not having enough capacity to push the .30 all the way out of the barrel as it takes more pressure so even if you upgrade your hop rubber you might not see better performance if your cylinder is undervolumed to push a 0.30g.
Take 5 shots at a chrono on 0.20gs and 5 shots with 0.30g with correct hop set(you might even find you can't get a good hop on 0.30gs and won't need to bother). Then compare results to see if your gun is now shooting 0.8j instead of 1.0j. You could gain MORE joules with heavier bbs or less if the gun can't handle it.
