You could still have air in the master, sucked in when you blew the line. The easiest way to bleed is to unhook the brake lines from the master, put a big ziplock over it, hold your fingers onto the holes where the brakelines attach (from the outside of the ziplock), and have someone else pump the pedal.
Like this the air will get out, but can't get back in (due to your finger pressure). much easier than bench bleeding, and less messy, as the fluid will be caught in the ziplock.
then just attach the lines and bleed the whole system.
the other possibility is that your rear shoes are way backed off, die you readjust them?
cheers,
J
