Contacted Lapua, Hornady and Nosler. The general consciences is unless you hammered the bolt closed and into battery, pushing just the shoulder back on a proper length/trimmed neck would not cause enough increased tension, squeeze, pinch on the bullet by the neck to cause a pressure spike of any significance. If the shoulder were that far out it would have to be very stretched, which would be an issue of a different matter. A small amount would cause the bolt to be hard to close, but would just cause the head space to be 0.