Your thread title suggests you want to sight in a scope. Your actual post didn't ask that. Generally I suggest setting the scope on the lowest power setting, in your case 3x and leave it there until you actually need to take a shot long enough that you have the time and need to adjust higher. This way you have the widest field of view and less noticable instability in your hold. You may never need to adjust much higher and if your shots come quickly you may never want to. Here in the west where our shots can be very long and its possible to catch an animal off guard and unaware...we have the time to adjust up and steady from a rest. Other places may not.