I don't know why, but when I tried 777 pellets in my Huntsman, I was getting misfires. Just to try it out, I bought a brand new box of 777 and fresh, dry 209 primers. First 2 loads misfired, 3rd fired o.k. and 4th misfired. Reloaded 14 more shots with pyrodex pellets, no problems. Yes, the gun was clean. No, there was no moisture or grease in the barrel or breech area. I'm stickin' with pyrodex. It has never let me down. I left the new box of 777 sitting at the range.