I can't speak to the encore platform but I shot a Striker in 308 for quite some time. Ballistics and actual game performance from the 14" barrel were quite satisfactory. Never had a problem with recoil or scope movement but again the Striker is a heavier gun. I can say that if I ever buy an Encore frame the first barrel I'm looking fro is a .308.
John A. Monroe, Never Forgive, Never Forget, Blood Pays Blood