I believe the force diagram is missing a very important opposing force. That would be the force of friction between the patched ball and the side wall. If that ball is really deforming during ignition of the black powder it may even change the force of friction as it travels down the bore.
Hi I am new to the muzzleloader forum. I started muzzleloading later in life in 2017. I will never forget showing up for a woods walk shoot at my local sportsmen’s club with a TC Hawken I purchased used. Though I checked the bore of that gun little did I know the nipple was filled solid with...