I was recently having a good natured discussion on another thread about whether cartridge case dimensions affect recoil. I don't think so but I've been wrong before. So educate me if I'm wrong. My impression is that recoil is dependent on rifle weight, bullet weight and velocity, and weight of powder charge. There could be other minor factors affecting recoil but cartridge dimensions is not one of them. The other view expressed, as I understand it, is that if all other things are equal, a short fat case will have more recoil than a long thin case. Reason being that the short fat case has a larger case head. Thus with equal psi the force pushing back on the bolt is greater. Thus greater recoil. I feel that until the bullet leaves the bore, pressure in the case is pushing equally in all directions, including the base of the bullet, and these forces, fore and aft, cancel out. After the bullet leaves the bore the jet effect of escaping gases greatly affects recoil. But prior to the bullet leaving the bore internal forces don't affect recoil. What do you guys think?