As a backpacker I can say that the Eberlestock rifle scabbard packs, the Just One in particular, are exactly what a hunter needs. Hands are free but the rifle is quick to come out.
I always backpack with two telescoping aluminum hiking poles. They assist me on climbs, stream crossings and save my knees on long downhills.
PLUS I can cross the pole straps and have an adjustable bipod very quickly.
But I can only use the hiking poles if my rifle is on my pack. So far I've used my Camelbak Commander backcountry ski pack for this, with the rifle strapped to the back. But a Just One is coming soon.
The Just one opens to hold at least one quarter of a deer or your emergency/overnight camping gear, your choice. This versatility is what I love about the pack.
On the con side all Eberlestock packs are so overbuilt that they run about 2 to 3 lbs. overweight. That's 2 to 3 lbs. of gear you must leave behind.