October 15, 2009, 10:51 PM
Natchez has a couple of these on sale for $59.+change. i want to replae 2 scopes on rifles i use mostly for taget shooting. they might be asked to take a crow, or some other small species occaaisoinally/ but most of the shooting will be at the bench. one is a tasco 4-12, non adjustable objective end. in this scope, i can adjust it so i can see the crosshairs or the target clearly @ 100 yards, but not both. the other is not nearly as bad, but is only a 3-9, which for the huntin rnd of it is fine. but when i am working up an accuracy load, i need to be able to see the crosshairs on the taget to line them up proprly.
October 16, 2009, 11:43 AM
i can adjust it so i can see the cross-hairs or the target clearly @ 100 yards, but not both.That should not be the case at all.
You adjust ocular lens focus so the cross-hairs are clear when pulling the scope up and looking through it quickly at the sky.
Once set that way, the cross-hairs will remain clear at any distance past the minimum focal length of the scope.
In the case of a 4-12x variable, that would probably be 15-20 yards or so at 4x, and perhaps 25-30 yards on 12x.
The reason for the AO on high power scopes is to dial out any parallax error at the exact distance you are shooting, and not so much to focus the scope so you can see the cross-hairs clearly through it at that range.
AO is not needed on scopes below about 10x, as parallax error is not as severe at lower powers. That's why you seldom see it on 3-9x and lower scopes. It just isn't necessary.
A target viewed at 100 yards through a 9x scope appears to be just 11+ yards away!
You can see .22 bullet holes at 100 yards with a quality 3-9x scope.
How much more power then that you need to shoot tiny groups is open to speculation.
The problems I have seen with cheap BSA and other Chinese scopes is non-repeatability of adjustments, a dim and narrow field of view at high power, and just not knowing what you are going to get from one scope to the next.
Fooling with a cheap scope that doesn't track right when you make click adjustments can quickly eat up your savings at todays ammo prices.
Not to mention your confidence in your shooting ability.