Like the others who have responded, I try to stay away from AO scopes for big game hunting. Most important reason: they are not necessary, and the less adjustments you have to worry about, the less you'll waste time fooling about with them in the field, and the less your chance of leaving them at a wrong setting and having to wonder if that was what caused you to miss... KISS!

Secondly, as somebody pointed out above, it is another system that can fail. If I'm not much mistaken, an AO also causes a slight loss of transmitted light - and why move in that direction for big game hunting?

As far as the stigmatism is concerned, I'm not an expert on these matters, but it would seem to me that the better option might be to get one of the European style adjustable oculars. Leupold (and other US manufacturers') also make adjustable oculars, but until recently, their adjustments were a lot more complicated than that of the European manufacturers. So,,,maybe a Zeiss Conquest or a Swarowski A-series would do the trick?? Nice scopes at still reasonable prices, in any event.
- mike

Correct me if I'm wrong. It is my understanding that the AO feature allowx you to set your scope parallax-free at a selected range, but it has nothing to do with FOCUS, which is adjusted at the ocular, rather than the objective, lens?? It addition, if one suffers from astigmatism, it takes a corrective lens in front of the eyeball to compensate for the warped lens in your eye. This is something no scope can correct for, unless the scope's lens system is ground to your prescription! This is not particularly practical, because astigmatism changes as your eyes change.

Eldeguello: I have a fleet of adjustable objective type scopes and indeed they ALL DO change the focus (clarity) of the image as they are set for diferent ranges!

All of these scopes also have ocular adjustment for additional image focus also.

I set my adjustable objective for focus at the range by turning it until it I can most easily read the lettering on my official bench rest targets. Usually (always?) this clearest focus distance is indicated closely to the distance my target is set up at. For instance at 100 yards the last AO scope I took to the range (last week) indicated about 90 yards on the AO dial when "focused"! This same clear focus setting of 90 yards also rendered "zero" parallax at 100 yards.

Yes indeed I have proven this AO adjustment changing also changes focus on scopes from low end to top end - Simmons to Unertl's.

If you do not have any AO scopes or have never used one try this - the next time you are at the range and see someone there with an AO scope just ask them to look through their scope. Then pick out some small lettering on a target and turn the AO. You will see the focus change.

I personally use AO scopes on all my Big Game, Target and Varmint scopes.

Next time you are in Antelope country take out your non-AO scope that is set from the factory at 150 yards. Then set up on an Antelope about 450 yards distant! Then move your eye from side to side and top to bottom of the available image. You will quickly learn how important it is to have an adjustable objective scope on your Big Game Rifles.

I have never had nor ever heard of an AO system breaking down and causing a Hunt wrecking situation!

I highly recommend the AO type scopes for Hunting where there is any possibility of a long shot.

Hold into the wind

VarmintGuy

All my rifles have Leopole A.O. scopes. Except my 416 it has a Burris fixed 23/4 and my 300 is fixed 6x.

For me to focus at 100 yards I have to set the AO at about 250-300 yards. I can shoot a non AO adequately at 100 yards but it ends up giving me a killer headache if I have to look through it for too long and I think it affects my groups some. I have contacts that correct part of my vision problem but they dont completely eliminate it. There are better contacts but I currently cannot afford them, they are about 300/pair. Thanks for the input guys.

My 22 mag has one for small game and targets but thats it and I have thought about getting rid of it,,,If I did not use it so much for targets I would.

I prefere fixed objective burris

Ocular lens is for focusing on the RETICULE. Objective lens is for focusing the IMAGE at the specific distance being shot, as well as eliminating parallax.



Having said that, quality scopes with non-adjustable objective lenses are more than plenty adequate for hunting purposes, both in regard to image quality and parallax out to any distance one can ethically shoot live, breathing, feeling animals IMHO. Plus, they are more compact, make the rifle a little tad less top heavy, give one less joint which can leak out nitrogen and leak in moisture, have one less joint which is loose enough to be movable at all, and generally are usually a wee bit smaller in external dimensions...which may help avoid hitting them against something in the field.



I have both hunted and shot competitively for over 45 years and have found no significant advantage to an AO scope in hunting.



Alberta Canuck

OK, Varmintguy! Thanks for the info! I've only had one scope with the AO feature, a Simmons 6X-18X, and at the higher powers, NOTHING improved the clarity of the view! Needless to say, I no longer have that scope (nor the TCR .22/250 it was mounted on!)