Scope Magnification

[cyclingbob]

Hi to All,

Preparing for North Berwick 9/13/14.

I have a BSR Sweet 22 3x9 with adjustable 40mm objective and 3" eye relief.

Currently using mag 6 but wondering what is recommended and reasons for recommendation.

I recall one post that at more than 6 for standing you will get sea sick.

I know I am focusing on the reticle and not the target so how does increased magnification effect that task?

Thanks a bunch.

Cheers.

Bob

[scuzzy]

Hi to All,

Preparing for North Berwick 9/13/13.

I have a BSR Sweet 22 3x9 with adjustable 40mm objective and 3" eye relief.

Currently using mag 6 but wondering what is recommended and reasons for recommendation.

I recall one post that at more than 6 for standing you will get sea sick.

I know I am focusing on the reticle and not the target so how does increased magnification effect that task?

Thanks a bunch.

Cheers.

Bob

Using an increased magnification level will exaggerate this small amount of 'wobble' that occurs. For example at 4x you will see the small movements that occur in all of us naturally. At 8x your reticle will really be moving about. In many people the amount of movement seen tends to disturb them.

You'll see a lot of movement occurring at higher magnification. A whole lot. It looks like you've got the shakes after a hard night out. And each increase in magnification multiples that effect.

Most instructors will tell you to crank your scope down to the lowest magnification level such as 4x. And that's good advice. At higher power many will freak out on the amount of movement seen. However that movement really isn't all that much - it just appears that way with a scope cranked way up.

Myself - I've cranked a Leupold up to 12x on a 25m target. Sure I see a bunch of movement. But at the same time the target is huge. But that didn't work so well at first until I got over the fact that there will always be movement. After I got over the movement I did really well. I should say I've got lousy eyesight and just love 12x even at short distances.

[Unbridled Liberty]

cyclingbob, are you over 50 and do you have progressive lenses?

UL

[AFTERMATH]

Hi to All,

Preparing for North Berwick 9/13/13.

I have a BSR Sweet 22 3x9 with adjustable 40mm objective and 3" eye relief.

Currently using mag 6 but wondering what is recommended and reasons for recommendation.

I recall one post that at more than 6 for standing you will get sea sick.

I know I am focusing on the reticle and not the target so how does increased magnification effect that task?

Thanks a bunch.

Cheers.

Bob

3x should be fine.
a)  You probably don't need anything higher.  As long as you can see your target, and place the cross-hairs on it.
b)  Higher magnification can lead to increased frustrations.
c)  Varying magnification can result in POI change - If you keep it bottomed out at 3X, it'll be there consistently

Don't fuss the "focus on the reticle"  Look at the reticle, it should be clear.  Place the clear reticle on target and watch the reticle to call your shots.

Remember, the targets we're shooting, and scoring are designed for iron sights.  Higher magnification will make it easier to hit the target.  So, unless you have a physical NEED for higher magnification - set it at as low as possible.  Earn it.

[slim]

cyclingbob, are you over 50 and do you have progressive lenses?

UL

[Agrivere]

Most shooters misunderstand the value of a scope. The real value of a scope is not in the magnification, but in placing the target and the sights in the same focal plane. This allows both the sights (reticle) and the target to both be in focus, something that's impossible with iron sights.

When you net it all out, the magnification is a mixed bag. It is often more of a distraction than a benefit, and I've seen many shooters struggle to really learn natural point of aim be amuse the scope makes it so easy to muscle the rifle onto the target without realizing it.

In short, your BSA scope is great, it will do just fine at 3x or 4x, but do be sure to adjust the parallax correctly as that is important.

[slim]

This allows both the sights (reticle) and the target to both be in focus, something that's impossible with iron sights.

That's also impossible with a scope.

Our eyes can't focus on two things at once.

[cyclingbob]

cyclingbob, are you over 50 and do you have progressive lenses?

UL

UL
Yes I do wear progressive lenses. I am 67.
I wear contacts to shoot so at least I am spared the complications of finding the sweet  spot with progressive lenses.

Thanks.

[2 clicks low]

cyclingbob, are you over 50 and do you have progressive lenses?

UL

I'm over 50 and have progressive lenses. Am I missing something? Scope works fine with my glasses. Peep sights have a blur from 12 to 2 o'clock due to the graduation.

Not too old to learn new info.

Thanks
2cl

[Guntuckian]

Most shooters misunderstand the value of a scope. The real value of a scope is not in the magnification, but in placing the target and the sights in the same focal plane. This allows both the sights (reticle) and the target to both be in focus, something that's impossible with iron sights.
...

Actually, it's not totally impossible with iron sights.  It just requires a hyperfocal focus with one's glasses.  The focus has to be set at twice the distance from the rear edge of the front post to one's retina.  Then, by a property of the hyperfocal focus, everything from half the hyperfocal distance to infinity is in an effective focus all at once.  I have a custom set of a Revision Sawfly goggles with prescription inserts set up this way.  They work.  The key is setting up the distances right.  (This is how Ansel Adams did his photographs of the West where everything appears to be in effective focus, simultaneously.  The so-called circle-of-confusion, or blur size, is about 1 MOA or slightly smaller.  A human eye cannot typically see much more detail than 1 MOA.)

--gb

[Guntuckian]

This allows both the sights (reticle) and the target to both be in focus, something that's impossible with iron sights.

That's also impossible with a scope.

Our eyes can't focus on two things at once.

Actually, yes, you can  effectively focus on two things at once if the two things appear to be at precisely the same distance from you, and are in the exact same plane, and are only slightly less than 1 MOA separated.

And, yes, you can effectively focus on both the front post and the target at the same time if there is only slightly less than 1 MOA difference between them, by using a hyperfocal focus with prescription shooting glasses.

It's like the old joke about a mathematician and an engineer in a room.  The rule is that for each successive step, they can only go half the distance of their previous step.  The mathematician laments that he can never get to the door to leave the room.  The engineer says it's not a problem, he can get close enough to the door to escape.

When the blur size is only slightly less than 1 MOA, then the entire image is in an effective focus, all at once.

-gb

[slim]

Could you explain how our eyes can focus on two things simultaneously?

[Long Shot]

Just as point of reference snipers will often use a fixed 10x scope for shots up to a mile. So 3x should be fine at 25 meters. Also the true beauty of a scope is not the magnification, it is the simplifying of the sighting system; you only have two things to focus (the reticle and the target) instead of three (the rear sight, the front sight and the target.) I personally think a 1x scope would be fine for 25m. ymmv

Hope this helps.

[Agrivere]

Could you explain how our eyes can focus on two things simultaneously?

We may be using different meanings of the word "focus", so I will try to clarify what I mean.  When I say "focus", I mean "in focus", i.e. the image the eye sees is not blurry.  Leaving aside Guntuckian's hyperfocal example for a moment, what I mean is that typically with iron sights, when we focus on the front sight post the target is usually at least slightly blurry.  If we shift the eye's focus to the target, the front sight post is usually at least slightly blurry.  Obviously given this choice, as shooters we want the front sight to be in crystal clear focus, and we don't worry about a slightly blurry target.  It's worth noting, though, that choosing a correctly sized aperture will bring the target into pretty good focus as well, but that's a whole 'nother topic!

When we switch to using a scope, the biggest advantage to shooting lies not in the magnification of the scope, but in the fact that the scope can bring both the "front sight" (in this case the reticle) and the "target" into the same focal plane, allowing both to be "in focus" (not blurry) at the same time.  If the scope is set up correctly (this is important - without an adjustable objective you are unlikely to be able to accomplish this at typical 25 meter Appleseed distances), then both the scope reticle and the target will be crystal clear, effectively allowing both the target and the reticle to be in focus.

What I think slim means here by focus is mental focus, or concentration, and I agree that it's extremely difficult to impossible to be mentally focused on more than one thing at a time.  Even with a scope, we want to "focus" our eye (i.e. concentrate) on the reticle, and not allow the target to distract us.  Since both the reticle and the target are "in focus" (i.e. not blurry) this can be difficult for some shooters and seeing the reticle moving around all over the face of the target can definitely be a distraction.  Hence the suggestion to use lower magnification, and I would wholeheartedly agree with Long Shot that for Appleseed purposes even a 1X scope would be perfectly fine, though I would suggest if the aiming point (reticle, red dot, whatever) is sufficiently fine, then a 1X scope would be sufficient out to most any distance where the target can be identified with the naked eye.

[Agrivere]

Actually, it's not totally impossible with iron sights.  It just requires a hyperfocal focus with one's glasses.  The focus has to be set at twice the distance from the rear edge of the front post to one's retina.  Then, by a property of the hyperfocal focus, everything from half the hyperfocal distance to infinity is in an effective focus all at once.  I have a custom set of a Revision Sawfly goggles with prescription inserts set up this way.

At the risk of bringing this thread far away from it's original topic, I did also want to come back to Guntuckian's comment about hyperfocal distance.  It's certainly true that many competitive shooters, mostly those with presbyopia (all of us in the 40+ crowd), will at least consider a prescription shooting lens that is adjusted to focus on a spot somewhere close to 2x the sight radius away from our eye - the hyperfocal distance. 

In theory this maximizes our depth of field, and allows both the front sight and target to be in reasonable focus.  In practice I'm not sure the reality holds up to the theory.  Remember that even though your prescription glasses give you a focal point set perfectly at your hyperfocal distance, your eye also has a lens, and it's not fixed.  When you are firing a shot, and your eye is focusing on the front sight, the lens in your eye will adjust (change) your focal point to a point as close as it can to the focal plane of the front sight.  The degree of this change will depend on many vision factors which are unique to each shooter, but I'm not sure it's realistically possible to take advantage of hyperfocal distance when shooting due to the fact that the lens in the eye will have a strong tendency to "mess up" your carefully crafted prescription.

In my experience what actually works much better is selecting the correct aperture.  Selecting the right aperture will present enough light to the eye for good vision without eye fatigue, but will be small enough to maximize depth of field.  Most younger shooters, for example, can get along just fine with an aperture as small as 0.38" in diameter.  For me, while apertures that small gave a great sight picture and depth of field, my eyes would fatigue too quickly, and I've increased my aperture size to 0.46" with much better results.  For comparison, it's my understanding that standard Tech Sight aperture size is .062" diameter, which is far, far too large to get much benefit from the aperture.

Once you get the right size aperture for your eyes, if you're shooting a service rifle (M14, M1 Garand, AR15), you can then if you wish get a set of match sights which include a small lens right in front of the aperture to adjust your focal plane even further if you wish.  I am not using it currently, but I've run a +0.25 diopter lens in my AR15 rear sight with good results.  Bob Jones sights, among others, has many different lenses available with different diopter settings (and even different colors).

My personal next experiment will be the use of the MISO sight system.  This is fundamentally a very tiny Fresnel lens which purports to provide a multifocal capability that allows everything to be in focus, from the front sight to the target and everything in between.  My initial examinations of it suggest that it seems to do exactly what it says it will do, but I've not yet installed it on my rifle to see if that holds up on the firing line.

[jmdavis]

The hyper focal distance is designed to provide a good front post while not degrading the target too much. That does not mean that they will both be "in focus" at the same time. For Service rifle I have settled on a +.75 addition to my distance scrip and use .040-.052 apertures. The variation is based on the available light. For example when shooting under a cover on an overcast day, I will switch to the .052. At Camp Perry I generally use a .042 or on really overcast days a .046 rear. But here is the thing. If you can hold well and if you can focus on the front sight (really focus), you can shoot that gray blob that is the target and do well at it.

The problem is that maintaining that front sight focus gets more difficult as the eyes tire, regardless of prescription. My eye doc is Triple Distinguished and I trust him about this stuff. On his advice I am wearing glasses, bifocals actually, most of the time now when I am not shooting. Further, I have prescription sun glasses as well. These changes, along with some changes to hold, have been really helpful over the past couple of months.

I see a much better target without the add to my script, but the front sight is too blurry to be used effectively. Getting old isn't easy. And getting old and shooting the Service Rifle is hard. But, hard does not equal impossible.

[jmdavis]

Just as point of reference snipers will often use a fixed 10x scope for shots up to a mile. So 3x should be fine at 25 meters. Also the true beauty of a scope is not the magnification, it is the simplifying of the sighting system; you only have two things to focus (the reticle and the target) instead of three (the rear sight, the front sight and the target.) I personally think a 1x scope would be fine for 25m. ymmv

Hope this helps.

On an AQT, my scores for scope and irons are within a couple of points of each other. We are talking fairly large targets. The main benefit to a scope, for me, is being able to see better. It helps with target ID, offers more ranging options, and it's single focal plan makes it easier to line up the reticle and the target.

For .22lr general use, I recommend a 4x fixed scope. A 2-7 or even a 3-9 are fine on the lower powers, but 4x will get you by just fine.

[Long Shot]

Just as point of reference snipers will often use a fixed 10x scope for shots up to a mile. So 3x should be fine at 25 meters. Also the true beauty of a scope is not the magnification, it is the simplifying of the sighting system; you only have two things to focus (the reticle and the target) instead of three (the rear sight, the front sight and the target.) I personally think a 1x scope would be fine for 25m. ymmv

Hope this helps.

On an AQT, my scores for scope and irons are within a couple of points of each other. We are talking fairly large targets. The main benefit to a scope, for me, is being able to see better. It helps with target ID, offers more ranging options, and it's single focal plan makes it easier to line up the reticle and the target.

For .22lr general use, I recommend a 4x fixed scope. A 2-7 or even a 3-9 are fine on the lower powers, but 4x will get you by just fine.

I agree whole heartedly, my hunting/appleseed rifle is an almost stock 10/22 with a weaver k-4 on it.

[Guntuckian]

There are two separate techniques being discussed here.  Pinhole camera aperatures work great, and will give you a very clear image and good depth of field, at the cost of field of view.  On the other hand, hyper focal lenses give you a good field of view with a very slight degradation of the target, while maintaining a crisp front post.  But, the big variable is light intensity.  The pinhole approach reduces the amount of light.  In bright light, pinholes work great.  In dim light, they do not work as well as hyper focal lenses.  As jmdavis points out, a hybrid approach can help optimize the front sight focus, at the expense of having the target not be in as good a focus, too.  But, there are ways to improve one's lot.  Aging is rough, but it beats the alternative!

-gb

[cyclingbob]

cyclingbob, are you over 50 and do you have progressive lenses?

UL

I'm over 50 and have progressive lenses. Am I missing something? Scope works fine with my glasses. Peep sights have a blur from 12 to 2 o'clock due to the graduation.

Not too old to learn new info.

Thanks
2cl

2cl

Please ignore my comment about progressive lenses above. I always shoot with contacts so I should be the last one to make a comment about progressive lenses. Ugh!
Thanks very much for the proofread.
Cheers,

Bob

[42769vette]

I don't know why anyone would recommend a fixed power scope anymore.  If you already have one that's one thing, but I always ask customers "what can you do on 4x, that you cant do with a 2-7".  The only answer is the ability to use your scope as a FFP (taking measurements) without the cost of FFP.

There was a time in the early 90's that we didn't have the technology/manufacturing ability to make a fixed power scope that didn't shift POI as you shifted zoom.  That time has come and gone, and they are not more expensive anymore.  If you have a fixed power scope use it, if your buying a scope buy variable.

[Unbridled Liberty]

Keep going, we only need 70 more replies to beat the parallax thread.

UL

[Long Shot]

I don't know why anyone would recommend a fixed power scope anymore.  If you already have one that's one thing, but I always ask customers "what can you do on 4x, that you cant do with a 2-7".  The only answer is the ability to use your scope as a FFP (taking measurements) without the cost of FFP.

There was a time in the early 90's that we didn't have the technology/manufacturing ability to make a fixed power scope that didn't shift POI as you shifted zoom.  That time has come and gone, and they are not more expensive anymore.  If you have a fixed power scope use it, if your buying a scope buy variable.

I just talked to a weaver rep and was told that the lenses and the coatings from the fixed (k-series) to variable power (v-series) are the same. With that being said I can go to SWFA.com and by a k-4 for $130 or 2-10x38 for $189. And fixed powers are know to be more rugged. - Those are some of the reasons why I lean towards fixed power scopes. - Your mileage may vary.

[jmdavis]

I don't know why anyone would recommend a fixed power scope anymore.  If you already have one that's one thing, but I always ask customers "what can you do on 4x, that you cant do with a 2-7".  The only answer is the ability to use your scope as a FFP (taking measurements) without the cost of FFP.

There was a time in the early 90's that we didn't have the technology/manufacturing ability to make a fixed power scope that didn't shift POI as you shifted zoom.  That time has come and gone, and they are not more expensive anymore.  If you have a fixed power scope use it, if your buying a scope buy variable.

The Army and Marine Corps might disagree with you. The beauty of a fixed power scope is that it is easy to operate, has no issues with changing reticle size with regard to magnification, and it is relatively inexpensive.

Those features may or may not be important to you. But they are important to some of us. My carbine wears a 4x Vadala M2. My silhouette rifle wears a Leupold 24x, my deer rifles a leupold 2-7, nikon 3-9, or nikon 2-7 all used on the highest power for any shot 50 yards or farther to minimize poi shift and ranging issues.

[42769vette]

I don't know why anyone would recommend a fixed power scope anymore.  If you already have one that's one thing, but I always ask customers "what can you do on 4x, that you cant do with a 2-7".  The only answer is the ability to use your scope as a FFP (taking measurements) without the cost of FFP.

There was a time in the early 90's that we didn't have the technology/manufacturing ability to make a fixed power scope that didn't shift POI as you shifted zoom.  That time has come and gone, and they are not more expensive anymore.  If you have a fixed power scope use it, if your buying a scope buy variable.

I just talked to a weaver rep and was told that the lenses and the coatings from the fixed (k-series) to variable power (v-series) are the same. With that being said I can go to SWFA.com and by a k-4 for $130 or 2-10x38 for $189. And fixed powers are know to be more rugged. - Those are some of the reasons why I lean towards fixed power scopes. - Your mileage may vary.

Ok K4 vs Vortex CS2 2-7 priced at 119.

Fixed power scopes are known to be more rugged to the people who have not followed the advances in optical design for the last 20ish years.  Today's variable power scopes are not the same scopes of 20 years ago.

[42769vette]

I don't know why anyone would recommend a fixed power scope anymore.  If you already have one that's one thing, but I always ask customers "what can you do on 4x, that you cant do with a 2-7".  The only answer is the ability to use your scope as a FFP (taking measurements) without the cost of FFP.

There was a time in the early 90's that we didn't have the technology/manufacturing ability to make a fixed power scope that didn't shift POI as you shifted zoom.  That time has come and gone, and they are not more expensive anymore.  If you have a fixed power scope use it, if your buying a scope buy variable.

The Army and Marine Corps might disagree with you. The beauty of a fixed power scope is that it is easy to operate, has no issues with changing reticle size with regard to magnification, and it is relatively inexpensive.

Those features may or may not be important to you. But they are important to some of us. My carbine wears a 4x Vadala M2. My silhouette rifle wears a Leupold 24x, my deer rifles a leupold 2-7, nikon 3-9, or nikon 2-7 all used on the highest power for any shot 50 yards or farther to minimize poi shift and ranging issues.

The only NEW fixed power scopes the military is buying is ACOG's (unless you want to count Aimpoint's).  Are there still fixed powers in theater?  Absolutly, but they are not what the military is buying, its what they have left over.  In my post I said the only advantage is the ability for the reticle to take measurements without paying attention to the zoom, or paying the money for FFP.

On a rare occasion the 10x SWFA will make sense, but that's because it has a ton on internal travel for the 300 dollar price range.

[yellowhousejake]

Cyclingbob,

Set the power to three and tape it there. Point your rifle into a clear blue sky and set the focus on the reticule alone until it is absolutely perfect. Do not look through the scope for more than 15 seconds at a time, and rest your eyes for five minutes between adjustments. It may take an hour to accomplish.

When you get to your Appleseed,

• Focus on the center of the reticule, always.
• Follow the six steps you will learn on Saturday morning diligently.
• Treat each step as you learn it as if that step alone were the ultimate secret to better marksmanship.
• Take extra time to contemplate how your position feels when you find your NPOA. Where are your legs? Where are your hands? How much are you leaning into the sling? Think about and remember those things each time you get into position.
• Enjoy yourself, shooting is supposed to be fun.
• Make it a point to help someone else during the weekend.

You may not get all your shots off, don't worry about it. Make every shot a good one and the speed will come as you progress. I tell my students seven shots in the five ring beats ten shots in the three ring, every time.

You will do fine.

DAve

[olefido]

Bob, do what Dave says, end of story.

This thread, the parallax thread, the rebranding thread, and the instructor activity thread remind me of another forum I belong to, rarely go to anymore, and haven't posted on in several months after several years of daily visits and several weekly posts.

Simple questions and questionable proposals receive multiple and sometimes conflicting replies. On the other forum, one person asked a simple question on whether one shirt should be worn tucked in to the trousers or not. The responses went on for 10 pages and ended up with one person quoting Title X of the US Code. This kind of stuff and a few forum members becoming the forum "thought police" are why I left. I don't want this forum to turn into that.

Sorry if I "bombed" your thread Cyclingbob, but it's been very frustrating watching things on here the last week or two and I needed to vent a little. No offense to you or anyone else and like I said, just do what YHJ says.

[Agrivere]

Conflicting replies are sometimes the way of things as we are all different and what works for one may not work for another. Personally I love hearing all of the differing perspectives as it gives me insight into points of view I may not have considered. I won't always agree, but I appreciate the dialog always.

I am also very aware that many - perhaps most - shooters are not interested in the details of hyperfocal distance or parallax or other fairly esoteric topics, but to some shooters they are critically important. I want to understand as much as I can both to improve my own shooting as well as to help others who may encounter marksmanship difficulties that I did not.

To me at least these sorts of debate/discussion threads are the most interesting, as these are great places to pick up ideas and knowledge I may not have considered. As an example, in a thread on some minutiae of reloading we got off topic into vision and eye fatigue, and jmdavis mentioned a little tip which has added 10 points at least to my scores.  If you're frustrated take a break. We will still be here when you get back.

[SPQR]

Bob, do exactly what Yellowhousejake said.