A seal assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a seal arc segment including a sealing portion, and a first rail and a second rail opposed to the first rail. The sealing portion extends in a circumferential direction between opposed mate faces and extends in an axial direction between a leading edge and a trailing edge. Each of the first and second rails extend outwardly in a radial direction from the sealing portion to respective first and second edge faces, and the sealing portion has a sealing face dimensioned to bound a gas path and includes a backside face opposed to the sealing face. Each of the first and second rails includes at least one interface bore dimensioned to receive a retention pin such that the seal arc segment is carried by the retention pin in an installed position. The seal arc segment is radially opposed to the sealing face between the first and second edge faces establishing a first region. The seal arc segment is radially opposed to the sealing face between the leading and trailing edges establishing a second region. A method of sealing for a gas turbine engine is also disclosed.