Just bought a 3d printed flip out single shot loader, it was tight going in and might have shaved a little off when I went to fire gun it just had the hammer sound no air,could putting the pellet in have caused it to push some of the plastic into the air port,after firing 30-40 times it got air back , now I just got a chrony and when I checked gun I was on max power 18 gr. Only getting around 770 fps.14 gr were only around 880, I know this gun should be over 900 fps ,barrel seal or possibly power adjuster seal, any ideas?