You should be able to get much better than a 5" group at 100 yards. If you aren't getting better then I would try another sabot and see how that one is shooting. These guns are tack drivers and 150 yards will be pretty easy as long as you pay attention to the slug drop and compensate for it. I guess it all depends where you set your zero. I might be inclined to sight in 2 inches high at 50 yards and see where that takes you. That should get you pretty close to a 100 yard zero.