Pachmyer forends for the Encore screw directly to the barrel, no hanger bar like their Contender models. Vertical stringing may be caused by how you rest the forend(assuming you're shooting off a rest). Assure that you rest in the exact same place on the forend and as close to the trigger guard as possible.
As Walt mentioned resting position can create vertical stringing. Another is head space issues,(shoulder not bumped back to match the chamber in your barrel).
I do have a Stratton hanger bar on one of my barrels. Its OK but I like the pillar bedded forend from Tony much better. They might appear expensive but after 3 trips to Wyoming they are worth every penny.