An open flow area test apparatus and test method for characterizing the performance of a sand control insert, such as slotted liner or wire-wrapped screen or other sand control apparatus. A sand control insert is set at or near the base of a pressure tight body, a sand pack is provided above the sand control insert, and a piston head applies a simulated overburden pressure to the sand pack. A test fluid is pumped through the sand control insert and differential pressures and sand flow through measured.