Ok, you just bought a custom 7mm Ajax Roadrunnner rifle. You've taken it to a local range and it shoots 1/2" 5 shot 100 yard groups off bags with factory ammo. You should be happy with that, You practice with some groups at 200 and 600 yards (what the range allows but how do know at that point if you're ready to hunt, and at what range. I'd suggest finding a place where you can shoot as far as you expect to hunt with the rifle. Make up some two foot square cardboard targets ( 6 or 7) and paint an 8" black spot (maybe 6 or maybe 10 depending on what you plan to hunt) in the middle of each. Then put them on 4 foot stakes and carry them into the field. Don't measure the distances, just put them in places where you can see they'll have a safe backstop at random distances. Then go back to a firing point and use the same equipment you expect to take into the field hunting. The same range finder (if any), the same wind meter (if any), the same supports (bipod, bag, sticks (if any), and the same range cards or calculator (if any). This assumes you've already zeroed your rifle at the range recently, but don't do that now. Then take one shot at each target using whatever aids you've brought which you think you need. (like the rangfinder). Have another person spot each shot but don't have them tell you where each shot hit, only record it . That person should have a good range finder and record the distance to each target. Repeat the set of targets a couple of times but don't shoot at the same target twice in a row. Then gather all of the targes and study them. This should give you a fair idea of what range you're good for deer or other big game hunting. It's no guarantee of hunting success, but you probably shouldn't be hunting at ranges beyond where you can regularly hit the targets in a controlled environment. I'm interested in now others determine what their practical capability is before they go hunting. That 5 shot group shot at the range from a bench means very little in my opinion. Certainly there's more to hunting than than just the ability to shoot, but I've seen too many "hunters' who go into the field and haven't even zeroed their sights.