You can get in 1 in 8" ,1 in 9" or 1 in 10" rate of twist. I have a Remington Model Seven that has a 1 in 9" ! I can shoot about any bullet with great accuracy with the 1 in 9" . With the Encore the 26" barrel would be your best bet I think. Who is makeing the barrel for you? And what do they recomend?
My favorite site: www.virginvalleyguns.com