ORIGINAL: todb
Their barrels have only been proofed to 10000 psi 150 grain loads will give you in excess of 25000 psi.
In fact, they are the only barrels which have been proofed. American muzzleloader barrels are not proofed.
100 grains of 777 in 2f granulation is allowed by the manual. This is equivalent to 115 grains of BP or RS. In terms of Peak Pressure, 110 grains of 777 is HIGHER than 150 grains of pellets. I figure, they don't want people putting 120 grains of 777 in their muzzleloaders so they limit
all powders to 100 grains. If you want more energy at the muzzle just use pellets or use 777 and you will stay within the guidelines.