Haven't had my Knight DISC out for a few years and pulled it out to warm up for ML season. Loaded a pair of 777 pellets just like always and pop, pulled everything, cleaned it all, and reloaded, pop again. Not really sure how old the pellets are, but at least 5 plus years and not stored in sealed. Do they expire or get old. Will probably go back to pyrodex pellets depending on what is available locally.