Some loads can have 5000 psi swings and less than 10 fps spreads. When you look at the pressure curves, you will see the area under the curve is the same, just shaped differently.
Thank you, Charlie. This now makes sense to me. Internal ballistics can be different and muzzle velocity relatively consistent. Friction would be one factor. Maybe, tool marks in throats/barrels and the bullet inconsistencies you mentioned. Alot of mysterious things going on in there. Jordan chasing upswing nodes in barrel movement with seating depth kind of blew my mind. I just wasn't thinking in the super slo-mo of interior ballistics regarding pressure curves while the bullet is still in the barrel. But, that one sentence turned on the light bulb. Thanks.
Andy
