1.25" at 100 yds isn't bad from your Encore. The one I had couldn't do better than 2.5" so I traded it off. It may have been a fluke I don't know but I was not impressed.
I personally clean a new barrel after each shot for the first 10, then after every 3 shots for the next 30. After that, I figure that all the minute burrs from machining are gone and begin load development.