Brakes

I replaced calipers and brake pads, mastercylinder and
roters (discs) I bench bleed mastercylinder twice till it was kind of hard to push screw driver in, I installed master cylinder and bleed the brakes beginng with right rear, left rear, right front, left front, each time the pedal would come up but when we stopped
bleeding and waited for 5 or so minutes then pumped again the pedal would again go to floor we did this like 5 times no signs of air. I can hear rear brakes moving but it seems like front caliper pistons are not moving out! What is the problem? Please help it is driving me nuts!
when I first checked the problem the right front caliper piston had frozen out and completly wore the brake pad down to bare metal. Could it have been the proportioning valve also? I can'nt figure it out
please help!