Longer seated bullets don't mean more pressure like handgun calibers. It's the opposite @Darkker . It's higher pressure if the bullet is jammed into the lands. But your other info is good. Pressure testing can only be achieved with the proper equipment hooked up to the pressure testing barrel. I think he's, the OP is referring to over pressure. All cases experience pressure. It's what safe for that chamber, Ackley or not. The case will tell you, like the pictures he provided