RAYFERD:NEVER SHOT A CHARGE OF 150 GRAIN.MAX IS 120GRAINS OF CLEAR SHOT. I REALLY THINK YOU WILL WASTE A LOT OF UNBURN POWDER FROM A 24 INCH. BARREL TO BURN COMPLETE 150 GRAINS OF LOOSE POWDER. 150 GRAIN CHARGE ARE PYRODEX PELLTES ONLY.AND THEY COAST A LOT MORE FOR PELLETS