A uniform interval treatment method features a plug with a breakable member in a passage set above a perforated interval so that pressure above the plug can be build up to the desired pressure that is high enough when the rupture disc breaks to deliver a burst of pressure at a level to overcome differential breakdown stress in the interval. A ball is then dropped on a seat on the same plug and captured so that it will stay on the seat when a gun is removed above. Another gun with a plug are delivered and the gun fired with the previous plug having a landed ball in the seat. The plug is again positioned above the just made perforations and the gun is removed. The rupture disc breaks to uniformly treat the next interval with a pressure to overcome differential breakdown stress of heterogeneous rock in the treated interval.