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Direct Link To This Post Posted: January/10/2010 at 08:07
biggreen747 View Drop Down
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8 Shot's Thanks for the additional info. I'm going to throw something out there for everybody to digest and I welcome any insight. Based on what I am seeing a scope that allows a generous amount of side to side eye position but without a parallax adjustment, while nice to use and possibly quicker to acquire targets with may not be in our best interest. Whereas one that is less forgiving will require a more proper cheek weld and shooting position and thus help reduce parallax error at longer ranges...
Direct Link To This Post Posted: January/10/2010 at 08:15
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Biggreen, I will agree with your statement.
What determines that "forgiveness" is exit pupil size, which is determined by magnification and objective size.
The least "forgiving" scope will thus have the smaller objective. Then the trade-off begins such as brightness in fading light etc.....
Direct Link To This Post Posted: January/10/2010 at 08:23
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And unfortunately as with everything there are always tradeoffs. 
Direct Link To This Post Posted: January/10/2010 at 09:49
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Thanks Wouter!  Good stuff as usual! 
 
Good shooting too, AS ALWAYS!
 
Gonna start calling you Steady Eddy!
 
If I had done that test the results would
have been a little more....umm...extreme! Embarrased
Direct Link To This Post Posted: January/10/2010 at 21:37
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Originally posted by 8shots 8shots wrote:

I will however concede and agree with JonA (and this burns my >>>> to do this), that shooting accurately at the longer distances without being parallax free takes a lot of concentration and effort.

Aww shucks, you make me blush.      Wink      Nice shooting.
Direct Link To This Post Posted: January/14/2010 at 02:50
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I've just got one question, and this is based on your mention of increased "concentration and effort"...Wink 
 
When you shot at 400yds with 100 yd parallax setting, did you just find a good full picture, aim, and shoot (the way the average joe who knows nothing about parallax would do), or did you take your time and center the error by moving your head up/down/left/right and finding the spot where the reticle travelled the same distance left/right/up/down from the bull??  Or..... did you back up on the stock until the edges got blurry, then center the now smaller picture in the eyepiece?? 
 
These are the two ways that I would use to lessen my error in a non adjustable scope, the first more accurate, the latter faster and easier....
Direct Link To This Post Posted: January/14/2010 at 02:56
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Originally posted by biggreen747 biggreen747 wrote:

8 Shot's Thanks for the additional info. I'm going to throw something out there for everybody to digest and I welcome any insight. Based on what I am seeing a scope that allows a generous amount of side to side eye position but without a parallax adjustment, while nice to use and possibly quicker to acquire targets with may not be in our best interest. Whereas one that is less forgiving will require a more proper cheek weld and shooting position and thus help reduce parallax error at longer ranges...
And this explains why the little Burris 4.5-14x32 is so sensitive to eye position on 14x.  Just holding it in my hand a local store, I couldn't keep it still enough to avoid blackness when the power was cranked up....
Direct Link To This Post Posted: January/14/2010 at 04:10
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Tbrake, the concentration and effort cam from using this system:
 
 take your time and center the error by moving your head up/down/left/right and finding the spot where the reticle travelled the same distance left/right/up/down from the bull
 
I tried backing off to have the edges blurred, but it seems more tricky, maybe because it forced my cheekweld into a position I was not comfortable with.
 
The reason for the scope being more sensitive at higher power to eye mnovement, is that as the power goes up, the exit pupil becomes smaller.
If you had a scope with a 1thou exit pupil, then parallax error would be largely eliminated. However, other problems would make the scope unusable.
Direct Link To This Post Posted: January/16/2010 at 18:48
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Originally posted by 8shots 8shots wrote:

Tbrake, the concentration and effort cam from using this system:
 
 take your time and center the error by moving your head up/down/left/right and finding the spot where the reticle travelled the same distance left/right/up/down from the bull
I don't have to tell you that your test has not proven anything for scopes without AO/side-focus Wink 
 
Your test has proven that you have good eyes, shooting skills, and a good understanding of parallax and how to correct for it.  Now set your scope to be parallax free at 100 meters, then hand it to someone who also has good shooting skills, but knows nothing about parallax or how to correct for it.  Have them shoot at 400 meters and see what happens.... This will represent the results of about 95% of the scope-buying public.
 
For example... my nonadjustable scopes that were factory set to be parallax free at 100 meters, had lots of parallax (8-10 inches of movement) when viewing the target at 600 meters. I could adjust most of this out with my adjustable scope to the point where they had little to no movement.  If I had handed my Mom (no clue about scope/parallax) both guns and had her shoot groups at 600 meters, what do you think would have happened??
 
In other words... I'm still convinced that adjustable parallax is always superior unless you intend to always shoot at one distance. 
 
I'm sure you also know that your head up/down/side/side method is pretty much impossible without having the gun benched on both ends.Big Smile
Direct Link To This Post Posted: January/17/2010 at 09:39
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all 8 is saying is that parallax isn't a big deal in the normal hunting shot. --regardless of distance.
 
off center parallax error from improper cheek weld isn't a problem when the eyeball is directly behind the optical center of the scope -- no matter who is shooting.
 
focusing parallax error is always there unless corrected by an ao (even if the eyeball is behind the optical axix) , and is a function of the objective diameter thus the smaller the objective the less parallax error.
 
higher magnifications -- magnify the error present depending on the amount there in the first place of the image projection behind the first set of lens.
 
in most variables below 15x the parallax error will be less then the cone of fire at distances beyond 300 yds.
 
trick with using a non ao scope, especially fixed power, is having a rifle/load combination that shoots as "flat" as possible to decrease the cone of fire (assuming its also a good grouper).
Direct Link To This Post Posted: January/17/2010 at 18:55
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Originally posted by Dale Clifford Dale Clifford wrote:

all 8 is saying is that parallax isn't a big deal in the normal hunting shot. --regardless of distance.

But that's not really what he showed.  If you need to shoot quickly, from a less than ideal field position, while choking down a case of buck fever (as is often the case when hunting), if you need to "take your time" and put forth "a lot of concentration and effort"--self imposed and in addition to everything else adding difficulty to the shot--you're not giving yourself the best chance for success.  
Direct Link To This Post Posted: January/17/2010 at 19:43
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to me it is --- the only thing that changes is the grouping of the intended point of impact.  which are well within the cone of fire. get a Pact timer and put it on yourself, whether under the pressure of competition or the hunt and try this with shooter ready positions standing.
Direct Link To This Post Posted: January/17/2010 at 20:31
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Again, "the only thing that changes is the grouping of the intended point of impact" could be stated as:

"the only thing that changes is the [Only thing that matters!]"

When the group moves from the vital zone to over the back of the animal or into its guts because you didn't take the time and go to the extreme effort required to center the reticle in the middle of the error zone as he described above, that's all that matters. 
Direct Link To This Post Posted: January/17/2010 at 22:24
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and again the kill zone is much larger than the parallax on any animal or human, even larger than the cone of fire in most cases. I found it interesting the 8s went to the trouble of illustrating it at distance. Parallax has its greatest problem in short range. This is seen almost every weekend in 3 guns matches. The parallax errors are there but less apparent because of the magnification of the optics used. (one of reasons to use a dot sight on the side of a higher variable.). and the low objective sizes. Use a 10 power on IPSC targets from 3 to 50 yards and the parallax is 4x his measurements, but will still be in the A zone. More errors (gut shots, etc) occur from hunters who have sighted in higher gain scopes at the highest power then returned them to the lowest for increased fov than errors from this parallax discussion.
Direct Link To This Post Posted: January/18/2010 at 00:05
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Originally posted by Dale Clifford Dale Clifford wrote:

and again the kill zone is much larger than the parallax on any animal or human, even larger than the cone of fire in most cases.

At close range.  This whole discussion began in a thread that was talking about error at 600 yds, which was observed to be 8"-10" through several scopes.  Expand your "cone of fire" with this additional "cone of error" and unless the vital zone you're going for is a chest shot on an elephant you had better do something to minimize it or not take the shot.

8s showed a good shooter who is cognizant of the error can take some time and deliberately apply specific additional techniques that will allow him to still make the shot (at 400 yds at least).  If he's in too big a hurry or forgets in the blur of pressure, or if a guy simply doesn't think parallax can be a problem and just points and shoots, he stands a good chance of missing his intended POI by a significant amount.  Yes, enough to completely miss an animal.

Quote Parallax has its greatest problem in short range.


Maybe in competition, where a tiny group isn't tiny enough if somebody else shoots a smaller one, or where targets are a certain number of MOA sized.  But in the real world the animals don't get smaller as they get closer to you.  Even a large angular (MOA) error at short range is less of a problem for hunting because the vital zone is that much bigger.  5 MOA off at 50 yds is no problem at all, 1 MOA off at 600 is unacceptable for the same sized target.
Direct Link To This Post Posted: January/18/2010 at 01:43
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The proof is in the pudding. I have hunted for more then 25 years using a telescope without parallax correction. During this time I have taken snap shots and deliberate shots. I have shot from prone, kneeling, standing and other awkward positions. I have stopped short of standing on my head. I have taken animals at 10 yds and at 600yds. The error induced by parallax error, has never been great enough to cause me to miss the vitals, which is mostly 12 inches or more in diameter.
I have a photographic file full of shot animals to proove this. 
The Test was "can a half decent shooter half this error by using CONSISTANT decent cheekweld." It was not whether your grandmother could do it. (unless she is a half decent shooter.) The point is, if your grandmother cannot do it, the equipment is capable and she can be trained to do it.
I have conceded that AO makes it a lot easier and less skill is required.
But Jon A, take what you want from this exercise, and remember the saying "with enough force, you can break anything".
 
T-brake, this discussion is based on whether it is "impossible" to shoot well enough without an AO. It was not about which system is superior. Every system has advantages and disadvantages and I am a great believer in that. I will never say one is better then the other. It all depends on your application which system is the best.
For example, we shoot a discipline were the shooter must take 5 shots under 1 min at targets that vary in distance from 180m to 350m. This hardly leaves one time to change positions and to engage different targets and to still focus the AO. This is a simulated hunting excercise were things change fast. The shooter that has the best advantage in this instance is one without AO, but can keep his eye on the optical path so as to eliminate parallax.
 
On the other hand, a target shooter with no time limit has all the time in the world to fiddle with an AO. He will be best served with a scope with AO.
 


Edited by 8shots - January/18/2010 at 04:27
Direct Link To This Post Posted: January/18/2010 at 04:39
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No, "The Test" was that even with a 25X scope with the parallax set at 100 yds, you wouldn't even notice a difference at 600 yds.  That was your original contention to which I disagreed.  Even though you haven't yet tested that far, I think even your 400 yd tests showed this is not the case, you certainly noticed the added difficulty.

The proof being in the pudding sounds good, but only if we know what's in your pudding.  A statistically significant number of animals at 600 yds taken with 25X scopes all with the parallax set to 100 yds?  With shots taken from odd field positions from uneven terrain when you only had a couple seconds to shoot?  If so, you must have some fantastic skills and I'd say you're right, that is good evidence supporting your argument.  But that's a big "IF."

I made it very clear in the first thread that low powered fixed parallax scopes can work just fine and so can somewhat higher power ones if you have them set for a longer range.  You contended it just wouldn't matter, even with high powered scopes even if the parallax was set for 100 because basically "people can't shoot any better than that anyway."  Hopefully this exercise has taught you that original contention was highly misguided.

With enough force you can break anything, and with enough desire you can come up with all sorts of crazy arguments why the things you like to use for other reasons are "just as good as" anything else for any other application.  People do it all the time.  You know if you must make the shot very quickly from an odd position you haven't practiced a bunch you will be less accurate with a 25X scope set to 100 at 600 yds.  Not your grandma, not somebody with less skill, but you.  Anybody would be. 

So your arguments that it's "good enough" are no different than arguing you don't need a 1 MOA rifle because a 2 MOA rifle will keep them all in 12" if your a really good shooter.  Surely you can see the pointlessness of such arguments.  It's not a difficult concept.
Direct Link To This Post Posted: January/18/2010 at 10:01
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A statistically significant number of animals at 600 yds taken with 25X scopes all with the parallax set to 100 yds?  With shots taken from odd field positions from uneven terrain when you only had a couple seconds to shoot?  If so, you must have some fantastic skills and I'd say you're right, that is good evidence supporting your argument.  But that's a big "IF."

This is done every weekend across the US in 3-gun and tactical matches.
Comparing scopes would be difficult because no two show the same image at the same power. (thread pitch, glass etc). The discussion is also mixing what occurs in the physical part of parallax and what action shooters call the flash sight picture. The error introduced into the shot by the sighting system. Good action shooters know the flash sight picture is off and will double the target if the shot breaks too soon, too late, hunting may or may not have this opportunity, but as Jon does suggest the results depend on practice. (which I would change the word to say training- which is different). Assuming the kill zone is 8 in dia. the only thing that changes with the distance is time on target. Using a z6 swaro set on 12 power with no parallax I can bang 8x10 steel all day (if the wind is good to me), today I'll try a 8x32 NF at 600 yds set on 50 yd parallax to see who is more accurate.
Direct Link To This Post Posted: January/18/2010 at 11:11
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Dale Thanks for stepping up to the plate. Just a tip. When setting the parallax at 50 yds your sight picture may be blurred. You can improve the focus by refocusing the eyepiece. You obviously then lose sharp focus of the reticule, but you will find a happy medium somewhere.
 
And JonA, as being "good enough" yes it can be. We shoot at 8inch gongs. A hit is a hit, whether dead center or a near miss.
 
Having shot this excercise, I still maintain that a parallax free scope will not make a person shoot better then with a scope with only 100m free parallax.
To start with, the same novice who has never shot at 600yds will not hit the targets first time, he will need to learn the disciplines of long range shooting. With that comes proper cheekweld, consistant eye placement etc. With that comes coping with parallax errors.
 
 
Direct Link To This Post Posted: January/18/2010 at 11:45
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I may have to shoot that genie Wouter if I ever see him!
Direct Link To This Post Posted: January/18/2010 at 12:18
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May I suggest a slightly different target that would be much more effective at reducing the needless controversy! 
Direct Link To This Post Posted: January/18/2010 at 13:36
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Originally posted by Dale Clifford Dale Clifford wrote:

This is done every weekend across the US in 3-gun and tactical matches.

But it isn't.  Nobody in the world uses 25X scopes for 3-gun.  Every 25X scope you'll find at a long range tactical match will have parallax adjustment.  I don't even know of any 25X scopes that don't have it.  For those using adjustable 25X scopes, I really doubt you'll find anybody who is in the habit taking down the 600 yd targets with the things set on 100.  Not anybody who wins anything anyway.

Thanks for offering to test with the NF.  For the sake of curiosity, try the test at both 8X and 25X.  It will be interesting to hear your results.
Direct Link To This Post Posted: January/18/2010 at 14:55
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sorry wasn't necessarily referring to the type of equipment used in either event, just that the level of shooters test suppositions in this post on a weekly basis. A lot of tactical shooters don't adjust for parallax, just isn't time, also one of the reasons alot use lower power variables - so they don't need to, however there a lot of 22x nxs used. While the 3 gunners use lower power scopes the lack of  distance makes the parallax problem more severe -- so in a way it evens out.

Just got back (have 1000 yd range with 10 mins drive) , used two rifles, and scopes, 8x32x56 NF and a 6x24x56 Diavari, which have extremely fine (and the best AOs I've ever used). Both will read distance on snap in focus to with 50 yds, but thats something else.  NF wouldn't focus on at 32 but would give a blur on 50 yd adjustment at 22x, which was used for test on .223 69 gr smk bc .375. Zeiss gave blur image at 50 yd adjustment and 24x with a slightly sharper image  using 175 smk bc .5. Had a diagonal wind in face, and all shots were taken off the hood of a pickup. (Snow is too cold to go prone). Bottom line -- If I could see the target (8x11 in steel plate) I could hit it and once the wind was doped the percentages went up. Test was also done at 750 yds, but the wind drift was killing the .223 and not conclusive. Granted the .223 would not have worked on prarie dogs, but I'm not sure if that was the clarity of the target or parallax. Didn't try it on 8x per suggestion, but will at a later date.
Direct Link To This Post Posted: January/18/2010 at 22:05
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Thanks for sharing the results, Dale.  Did you try and measure how much parallax error each scope had?  Just to be sure I'm reading you correctly, you say even after you had the wind doped your hit percentage was less than 100% on a vital zone sized target?

Anyway, thanks again. 
Direct Link To This Post Posted: January/19/2010 at 00:41
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Originally posted by Jon A Jon A wrote:

Thanks for sharing the results, Dale.  Did you try and measure how much parallax error each scope had?  Just to be sure I'm reading you correctly, you say even after you had the wind doped your hit percentage was less than 100% on a vital zone sized target?

Anyway, thanks again. 
 
If I could see the target (8x11 in steel plate) I could hit it 
( I also found that the image in the unfocused parallax shots were blurry and made accurate aiming difficult. )
 
"Just to be sure I'm reading you correctly, you say even after you had the wind doped your hit percentage was less than 100% on a vital zone sized target?"
Do not blame parallax for this....off the hood at 600 yds and you want a 100% hit?
Jon A, post some of your 600yd targets for us.
Dale, Many thanks for your tests. Excellent
It is interesting that you mention that in your 3-gun shoot there is not enough time to go with readjusting parallax. This was one of the starting points of this discussion, wherby I stated that I personally set my parallax somewhere midpoint to all the targets and bang away without readjusting, because there is just not time for continual re-focussing.
 
I hope we have now stuffed this genie back into the bottle!
 
 


Edited by 8shots - January/19/2010 at 04:19
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