Re: use this scope on my striker?
Most muzzleloader scopes have the parallax set to 50 yards. One reason they designate them as "muzzleloader" scopes. Most that I'm familar with also don't have AO's either.
I'd say you made the right choice on the Burris 3x-12x until you are ready for a rifle scope. Even then, you may decide to leave the pistol scope on it.