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View Full Version : is parallax a issue for a .22


smitherians
June 6, 2012, 01:30 AM
I was planning on shooting targets at 200-250 yards with my cz 452 in .22LR. I've been browsing scopes and I was wondering If parallax would effect groups at 250 yards. It's kinda a dumb question, but Im either getting a nikon 3x9 rimfire or mueller APV with adjustable AO. I've read that the nikon is a better quality scope but it doesn't have an adjustable objective. not really sure, need some help/recommendations. :confused:

Baylorattorney
June 6, 2012, 02:52 AM
It's my understanding that parallax for calipers other than 22 is set at 100yards. 22 is 65 yards. I got this when I bought a Leupold rim fire scope whose parallax was so set.

Norrick
June 6, 2012, 02:53 AM
Parallax adjustment in the form of adjustable objectives and side focuses, will tighten your groups, regardless of the caliber. How small do you want your groups is the question. To push a 22 out that far I would want as small as possible. People who hunt tend to shy away from them because its not going to make the difference between killed and not killed, plus some think its just one more thing to possibly break while in the field.


Ideally if you look down the center of the scope every single time, you don't need this adjustment, although we don't live in an ideal world, so it helps to eliminate this source of error when shooting.

Dave P
June 6, 2012, 02:57 AM
For shooting that distance with accuracy, you will want to zero out any parallax errors. Otherwise, accuracy will suffer if your eyeball is not in the same place for every single shot.

If it is not adjustable, I think most scopes are set for 50 or 100 yards ...

mete
June 6, 2012, 03:19 AM
AFAIK parallax for 22 and shotgun is 75 yds and others is 150 yds.I have a shotgun scope on my 45-70 because here I almost always take deer withing 50 yds.

madcratebuilder
June 6, 2012, 07:08 AM
I've read that the nikon is a better quality scope but it doesn't have an adjustable objective. not really sure, need some help/recommendations.

The Nikon Buckmaster and Prostaff scopes are nowhere close to the APV in quality. You would need to get in the Nikon Monarch series of scopes to match the APV's clarity and they cost 3X as much.

Magnum Wheel Man
June 6, 2012, 07:37 AM
Actually paralax needs most adjustment the shorter distances you shoot... so normally ( at "normal" distances the typical 22 is shot at ) paralax is very important... however the longer you shoot, the less adjustment is needed ( more adjustment is needed from 50ft to 50 yards, than is needed from 100 yards to 250 yards )

so if your non rim fire scope is adjusted for 100 yards, it will be much better suited to shooting long range than a non adjustable rim fire scope...

do you need an adjustable paralax to shoot long range... probably not, unless you are compitively shooting... but if you shoot from 50 ft to 200 yards, you might want & could use one more than if you were just going to shoot long range

Picher
June 6, 2012, 07:43 AM
If you want to shoot targets up to 250 yards away, a scope that can adjust to over 10x is advisable. The higher the power and the larger the objective lens necessary to achieve adequate brightness and clarity at the higher powers dictate a parallax adjustment, either by objective lens rotation, or turret on the side of the scope.

I like the 4.5-14X AO configuration for a combination target and hunting scope. At the lowest powers, the AO setting covers a longer distance spread, and at the higher powers, an accurate setting is more obvious and critical, especially at close to mid-range distances. My Mueller 4.5-14X holds it's own in clarity and consistency against many more expensive scopes.

Art Eatman
June 6, 2012, 07:55 AM
Like Magnum Wheel Man said, for centerfire scopes, parallax is mostly a problem inside 100 yards and less so beyond that. There is an ever-decreasing amount of parallax beyond 100 yards.

AO can improve the precision for a more consistent sight picture when shooting targets.

smitherians
June 6, 2012, 10:59 AM
Thank you all for your recommendations/help I think I'll pick up an APV from amazon:D

geetarman
June 6, 2012, 11:41 AM
The post below is from me a couple of years ago. I still stand by it with the caveat that parallax is a major error source when using high magnification at short ranges. Most applications using scopes for .22lr are going to be 100 yards and shorter. I cannot imagine using my .22 at 250 yards. For me it doesn't compute. If the 22 had a -250 behind it, that would make a world of difference.

Geetarman:D

***************************************************************
I am not sure I agree with your assessment of parallax and the effects of parallax on shot placement.

On scopes with non adjustable objective bells, parallax is generally set for 100 yards.

Parallax exists anytime the reticle and the target are not in the same focal plane and the apparent movement of the target and the reticle is significant at longer distances.

It is much more than just unscrewing the lens assy at the objective bell to "fix" parallax.

That feature is not built into lower quality scopes because it is expensive to do it.

The machining required to keep the objective bell internal thread axis parallel to the mechanical axis of the scope body is daunting. With out that, the shift of the reticle to a line of sight would give you a headache.

In any sort of optical tooling setup, proper establishment of a line of sight requires a set up at infinity as well as a close up target ( 2 feet or less ).

Without parallax correction, as soon as you buck the line of sight from infinity to the close target, you plunge and rotate the instrument and rebuck at infinity.

You will NEVER get a straight line of sight WITHOUT parallax correction.

If you have a parallax error of one arc second at 100 yards, you have an unknown of approximately 1 inch. That error gets proportionally larger as distance is increased if the end point cannot have that parallax error nulled.

On the other hand, a real error of 1 arc second at 500 yards is proportionally smaller as the range is decreased.

Parallax adjustments exist on high end scopes for a very good reason and that is not just so the manufacturers can charge more for them.

I did optical calibration for a major aerospace company for over 40 years and removing/reducing the effects of parallax is a major goal of successful calibration of alignment telecopes, jig transit squares and theodolites.

Geetarman

wingman
June 6, 2012, 06:39 PM
I find it interesting that the 22LR and 223 are being used at greater distance rifles each year on the net, any day I expect to open a thread to see a black bear killed at 1000 yards with a miracle 22 lr bullet.:D
Added note I have both calibers and use them often.

Bart B.
June 7, 2012, 10:41 AM
Folks, one cannot adjust parallax; they can only correct for it. And when the shooter's aiming eye's on the optical center of the scope as it looks through it, there's no parallax regardless of where the objective (front) lens is focused at.

I think it's stupid and irresponsible for rifle scope companies to call range focusing adjustment "parallax focus" or words to that effect.

geetarman
June 7, 2012, 11:27 AM
And when the shooter's aiming eye's on the optical center of the scope as it looks through it, there's no parallax regardless of where the objective (front) lens is focused at.

Quite true. The real rub is getting the rifle mounted so that your eye is in the same place every time. If you can achieve that, then parallax or no, you are good to go. If not, there is a problem.

It was always an issue when calibrating jig transit squares. When you looked at a guy setting up on the test stand, his eye would be moving side to side and up and down to get the best image of cross hair and optical target. Even in a lab environment, it was tough to do and get it right for every tool you checked.

The smallest errors always showed up in the floor shot where all the accumulated errors showed up. If you could not pass that, then you went back through the instrument test by test and tightening some and relaxing others until you could pass the floor shot.

It would make you proficient in another language...profanity.:rolleyes:

Geetarman:D

johnbt
June 7, 2012, 02:19 PM
"On scopes with non adjustable objective bells, parallax is generally set for 100 yards."

The last time I looked, Leupold set their fixed power scopes at:

150 yards for centerfire
75 yards for shotguns
60 yards for rimfire

The adjustable objective scopes I have like the large and small Leupold EFR scopes and both of the Weaver T-36 scopes adjust down to 10 or 11 yards. That makes them good for airguns at close range, although I use them mostly on rimfires at 50 yards.

John

johnbt
June 7, 2012, 02:22 PM
"The real rub is getting the rifle mounted so that your eye is in the same place every time."

Someone on rimfirecentral I think it was suggested putting a lens cap/cover on the scope after cutting a very small hole precisely in the center. That'll keep your eye aligned (and probably drive you nuts.)

geetarman
June 7, 2012, 03:09 PM
(and probably drive you nuts.)

I bet you are right. You would have a similar issue with an adjustable iris on a pair of glasses while shooting handguns. It may help you see the front sight on a handgun, but it will also slow you down.

Geetarman:D

chucknbach
June 12, 2012, 07:46 PM
http://www.opticsplanet.net/simmons-pro-target-matte-6-18x40-22-lr-turrets-riflescope.html

What I went with. I had a regular 3x9 Prostaff, the glass on this Simmons is way better.

I also have the 3x9 Pro Target both come with BDC and MOA turrents.

dvdcrr
June 16, 2012, 05:01 PM
yes it would affect groups by about a half inch at that range.

Chuck Dye
June 18, 2012, 11:50 AM
Parallax error only occurs if the shooter's eye is not aligned with the optical axis of the scope. The maximum error occurs when the eye is maximally off axis, aligned with the outer edge of the exit pupil. The Leupold owners' manual states that, for their 4x scope, that max is 8/10ths of an inch at 500 yards, less than 2/10ths inch at 100 yards. Even if you max the parallax error, it is likely to be lost in the noise of the rifle's inherent accuracy and the ammunition's inherent accuracy.

You can look here

http://rimfirebenchrest.com/articles/parallax.html

and do the math.

johnbt
June 19, 2012, 11:58 AM
If you are happy making your rifle shoot worse by using the wrong scope, well, that's okay by me. I'm trying to shoot better, not worse.

The math is fairly straightforward.

John

Slamfire
June 19, 2012, 01:18 PM
I was planning on shooting targets at 200-250 yards with my cz 452 in .22LR.

Parallax will be the least of your issues.

I regularly shoot small bore prone. A 5 mph wind change is enough to move a bullet from the center into the nine ring. That is why small bore shooters use wind gages, because no one can see a 5 mph wind change in the mirage.

Also, the elevation necessary to go from 100 yards to 200 yards is equal to the elevation it takes to go from 600 yards to 1000 yards with a 308. Around 24 MOA.

You will probably run out of elevation before you get there.

eldorendo
June 22, 2012, 06:59 AM
Folks, one cannot adjust parallax; they can only correct for it. And when the shooter's aiming eye's on the optical center of the scope as it looks through it, there's no parallax regardless of where the objective (front) lens is focused at.

I think it's stupid and irresponsible for rifle scope companies to call range focusing adjustment "parallax focus" or words to that effect.

A more likely possibility would be that the scope manufacturers actually understand parallax and you don't. :cool:

Boncrayon
June 23, 2012, 03:27 PM
Parallax is not as much an issue for a quality scope as it is for your eye lense protection (or possible astigmatism). I have 63 year old eyes. I have an astigmatism that forces me to close my left non-dominant eye. I shoot a Marlin 60 with a Nikon Prostaff 2x9x40 scope and at 50 yards, punched out my bull's eye with calibrated adjustments to the rectical. I wear extended cheap reading glasses. If I keep my head after following the distance and angle to the rear scope for full view, there are no problems. If I tilt my head at an upper angle to view the scope at the top of my reading lense, I get a parallax view. If I raise my chin to look directly into the scope, I do not have the problem. Be careful when adding eye protective glasses with your chin down, and missing the full field the scope offers.

B.L.E.
June 24, 2012, 08:57 PM
Parallax is a scope issue, not a .22 issue. All scopes have a specific range where the parallax is zero.

Take a scope that has zero parallax at 100 yards. Your eye is the gun's rear sight and the crosshairs are the gun's front sight. Optically, those crosshairs are 100 yards in front of your gun. When you shoot at something 500 yards away, moving your eye does the same thing as moving the rear sight of a gun with open sights. Moving your eye left moves the point of impact left.

When your target is 50 yards away, the "front sight" is 50 yards beyond the target and moving your eye left moves the point of impact right.

When your target is 100 yards away, the cross hairs are at the same distance as the target and moving your eye has no effect on the point of impact.

Many .22 specific scopes have zero parallax at 50-60 yards, reflecting the practical hunting range of a .22.

mrawesome22
June 24, 2012, 11:44 PM
I have to agree with Slamfire.

Attempting to shoot 22LR at 250yrds... parallax will be the least of your worries.

Groups? You mean patterns measured in feet.

Better get the broad side of a barn for a target. You'll need it.

Sent from HenseMod6.