Are you disappointed in the report produced by your 10FC or 105MM Big-Bang Cannon? This may be the reason it is not performing satisfactory. Conestoga Co. decided not to produce the charger plunger in two different sizes. Since the early 1990's they only produced the plunger sized for the 15FC and 155MM cannons. This plunger drops about 70% more Bangsite than the smaller cannon can use resulting in a sorry "poop" instead of the sharp report it is capable of. We don't sell the 10FC or 105MM for this reason.
To determine if this is your problem, remove the charger and measure the width of the slot in the charger plunger. If it is 3/16" wide then you have the plunger for the bigger cannon.
10FC/105MM 15FC/155MM 103 174 100 charges - weigh in grains: 1.03 1.74 Average charge - weight in grains: 67 113 Average charge - weight in miligrams: