Cleaning between shots is great but the sabot-bullet or power belt has to be a tight fit to begin with. Some will not snug up or shoot well unless the barrel is fouled. In my .50 knight, Dead centers and Nosler shots were the most accurate for me with a fouled bore. The plain jane Hornady sabot with 300 XTP was third, but it had the best point of impact when firing from a clean to a fouled bore. Only 1/2 inch difference. With most of the others there was as much as 6 inches at 50 yards. I had no problems with 777 accuracy, loose or pellets.