Long story shortish. Was camping last weekend and shooting the Maverick. It has about 500 pellets through it since new last year. On Thursday, I shot about 30 flawless pellets. Put it away in its case inside the camper. Saturday, I filled the gun from my great white tank and headed back to the bench. All of a sudden, the gun was shooting at a totally neutered fps. Ran 30 pellets through it and all were about as powerful as a daisy BB gun. Put gun away and moved on. Monday I was at home and ran the gun through the chrono and it was back on track and at its normal 875 fps. Any clue what the heck could have caused this? Elevation when camping was about 2000 ft higher than home, but the Maverick has fun flawlessly at camp before.