Riflescopes are mechanical contraptions. One of the sad realities about precision shooting is that, sooner or later, you will experience a scope failure. If you’re lucky it won’t happen in the middle of a National-level competition. And hopefully the failure will be dramatic and unmistakable so you won’t spend months trying to isolate the issue. Unfortunately, scope problems can be erratic or hard to diagnose. You may find yourself with unexplained flyers or a slight degradation of accuracy and you won’t know how to diagnose the problem. And when a 1/8th-MOA-click scope starts failing, it may be hard to recognize the fault immediately, because the POI change may be slight.
When An Expensive Scope Goes Bad
Recently, this editor had a major-brand 8-25x50mm scope go bad. How did I know I had a problem? Well the first sign was a wild “drop-down” flyer at a 600-yard match. After shooting a two-target relay, I took a look at my targets. My first 5-shot group had five shots, fairly well centered, in about 2.2″. Pretty good. Everything was operating fine. Then I looked at the second target. My eye was drawn to four shots, all centered in the 10 Ring, measuring about 2.4″. But then I saw the fifth shot. It was a good 18″ low, straight down from the X. And I really mean straight down — if you drew a plumb line down from the center of the X, it would pass almost through the fifth shot.
That was disconcerting, but since I had never had any trouble with this scope before, I assumed it was a load problem (too little powder?), or simple driver error (maybe I flinched or yanked the trigger?). Accordingly, I didn’t do anything about the scope, figuring the problem was me or the load.
But, at the next range session, things went downhill fast. In three shots, I did manage to get on steel at 600, with my normal come-up for that distance. Everything seemed fine. So then I switched to paper. We had a buddy in the pits with a walkie-talkie and he radioed that he couldn’t see any bullet holes in the paper after five shots. My spotter said he thought the bullets were impacting in the dirt, just below the paper. OK, I thought, we’ll add 3 MOA up (12 clicks), and that should raise POI 18″ and I should be on paper, near center. That didn’t work — now the bullets were impacting in the berm ABOVE the target frame. The POI had changed over 48″ (8 MOA). (And no I didn’t click too far — I clicked slowly, counting each click out loud as I adjusted the elevation.) OK, to compensate now I took off 8 clicks which should be 2 MOA or 12″. No joy. The POI dropped about 24″ (4 MOA) and the POI also moved moved 18″ right, to the edge of the target.
For the next 20 shots, we kept “chasing center” trying to get the gun zeroed at 600 yards. We never did. After burning a lot of ammo, we gave up. Before stowing the gun for the trip home, I dialed back to my 100-yard zero, which is my normal practice (it’s 47 clicks down from 600-yard zero). I immediately noticed that the “feel” of the elevation knob didn’t seem right. Even though I was pretty much in the center of my elevation (I have a +20 MOA scope mount), the clicks felt really tight — as they do when you’re at the very limit of travel. There was a lot of resistance in the clicks and they didn’t seem to move the right amount. And it seemed that I’d have four or five clicks that were “bunched up” with a lot of resistance, and then the next click would have almost no resistance and seem to jump. It’s hard to describe, but it was like winding a spring that erratically moved from tight to very loose.
At this point I announced to my shooting buddies: “I think the scope has taken a dump.” I let one buddy work the elevation knob a bit. “That feels weird,” he said: “the clicks aren’t consistent… first it doesn’t want to move, then the clicks jump too easily.”
Convinced that I had a real problem, the scope was packed up and shipped to the manufacturer. So, was I hallucinating? Was my problem really just driver error? I’ve heard plenty of stories about guys who sent scopes in for repair, only to receive their optics back with a terse note saying: “Scope passed inspection and function test 100%. No repairs needed”. So, was my scope really FUBAR? You bet it was. When the scope came back from the factory, the Repair Record stated that nearly all the internal mechanicals had been replaced or fixed: “Replaced Adjustment Elevation; Replaced Adjustment Windage; Reworked Erector System; Reworked Selector; Reworked Parallax Control.”
How to Diagnose Scope Problems
When you see your groups open up, there’s a very good chance this is due to poor wind-reading, or other “driver error”. But my experience showed me that sometimes scopes do go bad. When your accuracy degrades without any other reasonable explanation, the cause of the problem may well be your optics. Here are some of the “symptoms” of scope troubles:
1. Large shot-to-shot variance in Point of Impact with known accurate loads.
2. Uneven tracking (either vertical or horizontal).
3. Change of Point of Impact does not correspond to click inputs.
4. Inability to zero in reasonable number of shots.
5. Unexpected changes in needed click values (compared to previous come-ups).
6. Visible shift in reticle from center of view.
7. Changed “feel” or resistance when clicking; or uneven click-to-click “feel”.
8. Inability to set parallax to achieve sharpness.
9. Turrets or other controls feel wobbly or loose.
10. Internal scope components rattle when gun is moved.
Source of Problem Unknown, but I Have a Theory
Although my scope came with a slightly canted reticle from the factory, it had otherwise functioned without a hitch for many years. I was able to go back and forth between 100-yard zero and 600-yard zero with perfect repeatability for over five years. I had confidence in that scope. Why did it fail when it did? My theory is side-loading on the turrets. I used to carry the gun in a thick soft case. I recently switched to an aluminum-sided hard case that has pretty dense egg-crate foam inside. I noticed it took some effort to close the case, though it was more than big enough, width-wise, to hold the gun. My thinking is that the foam wasn’t compressing enough, resulting in a side-load on the windage turret when the case was clamped shut. This is just my best guess; it may not be the real source of the problem. Remember, as I explained in the beginning of this story, sometimes scopes — just like any mechanical system — simply stop working for no apparent reason.
As a Father’s Day Promotion, Bushnell is offering rebates on Trophy XLT and H20 full-size binoculars and a GPS tracker for hikers/hunters. CLICK HERE to learn more about these “Deals for Dad” which are valid from today (May 11, 2013) through June 16, 2013.
Promo found by EdLongrange. We welcome reader submissions.
Gary Eliseo of Competition Machine is now (again) manufacturing adjustable heads for spotting scopes. These work great for High Power, Three Position, Across-the-Course, Prone, and F-Class shooting. The head fits on a scope stand, so it can adjust to any height you need. This is a super-high quality unit according to our buddy Dennis Santiago: “They’re back — the best scope head on the planet is back in production. Direct from Gary Eliseo this time. Uses any 3/4″- or 1″-diameter shaft stand.”
Gary tells us: “I had so many people ask me to bring my scope head back into production I thought I’d try a trial run to see how they were received. Well, the first run nearly sold out just by word of mouth! I do have some still available from the first run, and we’ll do another run. Price is $185.00 plus shipping. You can choose from 12 Cerakote colors.”
Eliseo Universal Scope Head Features
Scope Head can be mounted above or below scope body.
Scope Head works for both right-handed and left-handed shooters. 6.25″ Offset.
Scope Head works with 3/4″-diameter and 1″-diameter uprights.
Integral dovetail mount (saves wear and tear on spotting scope base threads).
Coarse and fine elevation settings require no tools to adjust.
Adjustable windage disc brake friction.
The Competition Machine Universal Scope Head is available right now — a few units are left from the first production run. To order, call 714-630-5734. To see other Competition Machine products, including tube gun chassis kits, visit www.GotXring.com.
Ever wish you could see the image from your riflescope on a large bright screen, and record your shooting experience when shooting targets or hunting? Well, here’s a new product that offers that functionality. The iScope is a handy adapter that connects a smartphone to your rifle scope — virtually any scope. You can see your target and cross-hairs easily without squinting and with your head in a comfortable position. Importantly, the image from the scope can be seen easily from a few feet away, allowing an instructor to provide guidance during the shooting process.
Jeff Foxworthy iScope Promo Video
(Install, App Launch, and Zoom at 1:10)
To use the iScope, you need a $0.99 App that allows you to zoom the image with a slider on your smartphone. This app also operates the Record on/off function, so you can record video clips. These can later be uploaded to YouTube and social media sites. Show the world your great bughole group, or your successful game hunt.
Practical Advantage of Digital Viewing We think this product (or something like it) will be very valuable during training. The large view-screen allows instructors to “see what the shooter sees”, so the trainer can provide immediate feedback to the trainee. In addition, while practicing at long range, a shooter can record the position of wind-flags, or record mirage for later analysis. During a match, the iScope could be used by match directors to record shot placement, with a “shooter’s eye view”.
The iScope also offers obvious benefits for shooters with physical disabilities. Head positioning is critical with rifle optics — you must align your eye very precisely with a small circle of light (exit pupil) only a few millimeters in diameter. With a large viewscreen, a wheelchair-bound shooter can position himself comfortably and view the magnified scope image.
iScope Benefits
Shooting sessions can be recorded and reviewed later.
Digital Zoom allows greater magnification with low-power optics.
Shooters with eye problems can see target and cross-hairs more easily.
iScope helps Shooters with physical disabilities.
The iScope retails for about $110.00 ($99.00 on Amazon). All iScopes come prepackaged to fit the iPhone 4/4S or iPhone 5 at this time. However, you can purchase other backplates to fit popular Android OS smartphones from Motorola and Samsung. The iScope is versatile — it fits nearly all rifle scopes and there is an adapter for spotting scopes also.
Forum member Keith T. (aka “KT”) is in the U.S. Navy, so he has a fondness for seafaring, nautical color-schemes. Here is KT’s new F-Open rifle, smithed by Accurate Ordnance out of Winder, Georgia. The gun is chambered in .284 Winchester for Lapua brass (necked up) and 180gr Berger Hybrids.
KT admits, “It’s a little bit different than most in appearance!” But KT likes it that way: “When I had Accurate Ordnance build it, the only thing I specified was the stock, action, caliber and barrel length. I left the rest up to them. I think they did a pretty awesome job.”
The gun features a Pierce cone-bolt long action (with Jewell trigger) in a McMillan F-Class stock. The barrel is a Brux 31″, 1:9″ twist in the Brux “F-Class contour”. Sitting on top is the new Nightforce 15-55x52mm Competition scope with turrets and sun-shade coated blue to match the blue-coated action, bolt handle, rings, trigger guard and barrel.
The build came out great, but there were a few “bumps on the road”. KT explains: “This rifle took a long time to finish. When it comes to building guns I always joke and say if it weren’t for bad luck I wouldn’t have any luck at all. We started ordering parts in September 2012. Somehow I managed to order the stock from McMillan for the wrong Pierce action. After a bunch of scrambling and hard work on Accurate Ordnance’s part we were able to get my screw-up fixed. Then we ran into a few more snags. AO wanted to have the scope on hand before doing the coating. The first trigger was not up to standard with AO so they ordered another one and the list goes on. The rifle is finally done though and I couldn’t be happier.”
Nightforce Optics will unveil new products at the NRA Annual Meetings and Exhibits this upcoming Friday. The big news is an 82mm spotting scope — the first-ever spotter from Nightforce. We knew Nightforce was planning an important product launch, but frankly this announcement caught us by surprise — Nightforce has always been a riflescope company. This is new territory. Why is Nightforce rolling out a high-magnification spotting scope now? Kyle Brown, Nightforce’s Director of Sales and Marketing, explains: “Our customers have asked for many years when we would introduce a spotting scope. The answer was, ‘at a time when we could produce a spotting scope equivalent in performance and quality to Nightforce riflescopes.’ That time is now.”
The new TS-82™ Xtreme Hi-Def™ spotting scope features a large 82mm objective, plus high-quality, European-made APO Fluorite Glass. The “street price”, including a 20-70X eyepiece, should be $2522.00 ($2600 MSRP). Shown above is the straight-body version, but the TS-82 will also be offered with an angled body for the same price ($2522.00 including 20-70X eyepiece). Nightforce promises that, by the end of 2013, an optional wide-angle 30-60X eyepiece will be available. In addition, Nightforce plans to offer an accessory mount for attaching a red dot sight or a laser rangefinder. This is good news for long-range hunters — you can locate your target through the spotter and then instantly range distance-to-target with an LRF aligned precisely with the spotting scope lens. Nightforce will also offer a handy iPhone accessory mount for digiscoping.
At the NRA Meeting in Houston, Nightforce will also introduce a new, side-focus 2.5-10x42mm NXS riflescope. For years, the Nightforce 2.5-10x32mm NXS Compact has been a popular optic. The new Nightforce 2.5-10x42mm NXS Compact, with its larger objective, should be more effective in low light. Yet the scope is still fairly light-weight (19 oz.–20.5 oz.) and compact (11.9 inches in length). Expect “street price” to be around $1740.00.
The notable feature of the new 2.5-10x42mm NXS is its side parallax adjustment (25 yards to infinity). It’s unusual to find side parallax control on an optic with 10X max magnification. The new 2.5×10 also incorporates red or green reticle illumination with adjustable intensity settings. Six different reticles are available, including the new IHR™ (International Hunting Reticle). The 2.5-10x42mm is offered with .250 MOA Hi-Speed™ or .1 Mil-Radian adjustments on exposed turrets, or, alternately, enclosed (capped) turrets with .250 MOA clicks. For more information, visit NightforceOptics.com
Need a hunting scope? With Nikon’s recently-announced Spring Shooting Savings promo, you can get $30.00 to $50.00 instant savings on select Nikon Buckmasters® riflescopes. The promotion runs from April 22 through May 30, 2013. For more information, visit www.NikonPromo.com.
Nikon Buckmasters riflescopes feature multicoated lenses, 1/4-MOA clicks, and up to 92% light transmission. Nikon claims that all Buckmasters riflescopes are waterproof, fogproof, and shockproof. Here are the models with instant savings:
Hunters and tactical shooters need scopes with good low-light performance. For a scope to perform well at dawn and dusk, it needs good light transmission, plus a reasonably large exit pupil to make maximum use of your eye’s light processing abilty.* And generally speaking, the bigger the front objective, the better the low-light performance, other factors being equal. Given these basic principles, how can we quickly evaluate the low-light performance of different makes and models of scopes?
Here’s the answer: ScopeCalc.com offers a FREE web-based Low-Light Performance Calculator that lets you compare the light gain, perceived brightness, and overall low-light performance of various optics. Using this scope comparison tool is pretty easy — just input the magnification, objective diameter, exit pupil size, and light transmission ratio. If the scope’s manufacturer doesn’t publish an exit pupil size, then divide the objective diameter in millimeters by the magnification level. For example a 20-power scope with a 40mm objective should have a 2mm exit pupil. For most premium scopes, light transmission rates are typically 90% or better (averaged across the visible spectrum). However, not many manufacturers publish this data, so you may have to dig a little.
ScopeCalc.com’s calculator can be used for a single scope, a pair of scopes, or multiple scopes. Once you’ve typed in the needed data, click “Calculate” and the program will produce comparison charts showing Light Gain, Perceived Brightness, and Low-Light Performance. In the example below, we compared a “generic” 5-18×50 Tactical scope with a “generic” 8-32 Benchrest scope.
Though the program is easy to use, and quickly generates comparative data, assessing scope brightness, as perceived by the human eye, is not a simple matter. You’ll want to read the annotations that appear below the generated charts. For example, ScopeCalc’s creators explain that: “Perceived brightness is calculated as the cube root of the light gain, which is the basis for modern computer color space brightness scaling.” In addition, the way ScopeCalc measures Low-Light Performance is pretty sophisticated: “Low Light Performance [is calculated] as the average of light gain and resolution gain through magnification, as a measure of target image acuity gain in low light similar to Twilight Performance specified by scope manufacturers. Low Light Performance calculated here is much more useful than Twilight Performance, as Twilight performance is the average of the just the objective lens diameter times magnification, while Low Light Performance is the average of the actual Perceived Brightness times magnification, which also includes the exit pupil/eye pupil relation, light transmission, approximated diffraction, as well as the perception of relative light gain. Just as with Twilight Performance, this Low Light Performance calculation does not yet include lens resolution and contrast as factors. Therefore lower quality optics will yield relatively less gains at higher magnifications.” Got that?
*In low light, the human eye can typically dilate to 5mm – 7mm. The exact amount of dilation varies with the individual, and typically declines, with increasing age, from 7mm (at age 20) to a dark-adapted pupil of about 5.5mm by age 65. To take full advantage of a scope’s light-gathering capacity, the diameter of an eyepiece exit pupil should be no larger than the max diameter of your eye’s dark-adapted pupil, so that all of the light collected by the scope enters your eye, rather than falling on the iris. A large 8mm exit pupil may seem good, but it would be partly “wasted” on a shooter in his 60s.
Some times nice guys do finish first. Our buddy Vu Pham, co-founder of the NorCal Practical Precision Rifle Club (NCPPRC) took top honors in the NCPPRC monthly tactical long range match on the 1000 yard range at the Sacramento Valley Shooting Center. Shooting his .260 Remington in a McMillan A5 stock, built by Spartan Rifles, topped with a Bushnell 4-30x50mm from CS Tactical, Vu beat a competitive field on a breezy day that saw the top 6 shooters separated by only 15 points. The Course of Fire had 27 of the 50 rounds shot from 800 to 1000 yards, where the fast-switching winds at 1000 yards were the deciding factor in the outcome. Vu tells us: “This LR Match win has eluded me for seven years now with these guys. I’ve been in the top five quite a few times, but never took home the win. Our matches are so close these days that it usually comes down to one or two bad trigger presses or ‘blown’ wind calls to separate the Top 10 shooters.”
NCPPRC long range tactical matches are held the first Sunday of each month, and are open to anyone 18 or older. No membership in any organization is required. Registration is at Range 12 of the Sacramento Valley Shooting Center from 07:30 to 08:30 in the morning. Cost is $25. To learn more about the match visit the NCPPRC Long Range Match webpage.
New Bushnell 4.5-30x50mm Tactical Scope
Vu Pham was running an all-new Bushnell front focal plane 4.5-30x50mm XRS scope with an amazing 6.7 times zoom range. This 34mm-tube scope features Bushnell’s G2 DMR Reticle. For a scope offering 30X magnification, is it compact at 14″ OAL (only 3/4″ longer than the HDMR). The elevation turret provides 10 mils per revolution with a zero stop. The scope sells for $2149.00 at CS Tactical.
Vu liked the new Bushnell scope and, obviously, it performed well for him. Vu tells us: “I believe this optic just hit the market… and is still pretty new. After having a few days behind the Bushnell XRS 4.5-30, I believe this optic will be a very viable option for the tactical precision rifle game. One of my favorite features of this scope is the mil-based G2DMR reticle. It makes holding over (and holding for windage) fast and easy. I will be doing a full test and evaluation in the next week or two after I get more time behind the optic.” Mike Cecil with CS Tactical provided the scope for this T&E.” Mike notes: “This is not the 4-30 tactical that’s listed as an XRS in the Bushnell online catalog — that’s a 30mm in the 6500 series line. This 34mm-tube XRS is a whole new animal!”
With the advent of its new-for-2013 scope models, Nightforce is discontinuing some of its popular NXS scopes. Now you can save hundreds on the Nightforce 3.5-15x56mm NXS and 12-42x56mm NXS.
Since its introduction, the big 12-42 NXS has always been one of the most popular and successful long-range and target scopes, and now you can save big bucks. Eurooptic.com has dropped the price on the 12-42x56mm NXS (various reticles) from $1981 to $1700 — that’s a $281.00 savings*. Both .125-MOA-click and .250-MOA-click turret models are on sale. Likewise Eurooptic.com has just slashed the price on the 3.5-15x56mm NXS from $1862 to $1599 — a $263.00 savings. NOTE: These big discounts apply to in-stock inventory on discontinued models only. When the supply is gone, it’s gone.
To order, visit Eurooptic.com or call (570) 220-3159 and ask for Jason. Available inventory and reticle choices are shown on the website.
*C330 Model with NR-R2 reticle is $1750; C331 Model with NP-R1 reticle is $1800.
If you want a March scope, now’s a good time to buy. Jim Kelbly of Kelbly’s Inc. has announced that, during the month of April, “March Scopes are being reduced by 10% for any March Scope in inventory.”
Jim adds: “We have a number of March scopes in inventory and many of the most popular models are [in-stock now]. So give us a call here at Kelbly’s at 330-683-4674 if you would like to purchase a March Scope or check inventory.”
Remember — if you snooze, you lose. The folks at Kelbly’s expect the in-stock inventory of the most popular March scopes to sell out fast. NOTE: This 10% savings offer is limited to March scopes currently in-stock at Kelbly’s. Backordered items or units to be delivered in the future are not discounted.
Nikon has introduced an all-new line-up of affordable riflescopes for hunters and varmint shooters. The new Nikon ProStaff 5 Series of scopes feature four times zoom range and a bright new optical system. With their fully multi-coated lenses, ProStaff 5 riflescopes provide up to 95% light transmission. That’s great for hunters working at dawn and dusk. (Some ProStaff 5s also have illuminated reticles). All ProStaff 5 scope models are waterproof, fogproof, and shockproof.
The ProStaff 5 line-up of scopes ranges from 2.5-10X to 4.5-18X with a variety of reticle options including NikoPlex, BDC, Fine Crosshair with dot, and Mil-Dot. Some ProStaff 5 scopes have an illuminated reticle with five intensity levels of red or green. A rheostat dimmer is located on the side focus knob for easy adjustment. All ProStaff 5 scopes now offer spring-loaded, instant zero-reset turrets. This makes your return-to-zero fast and foolproof in the field. (To set your zero, just sight-in as usual, then lift the spring-loaded adjustment knob, rotate to “zero,” and re-engage.)
ProStaff 5 series scopes were designed with a constant (and generous) four inches of eye relief. If you’ve ever had to move your head back and forth as you changed magnification levels, you know that constant eye relief is a big deal with very real practical benefits in the field. The new ProStaff 5 scopes also feature a quick-focus eyepiece, to allow any shooter to easily bring the reticle into focus.
Nikon ProStaff 5 Scopes
Part # Model Reticle MSRP
6735 2.5-10×40 Nikoplex $269.95
6736 2.5-10×40 BDC $279.95
6737 2.5-10×40 (silver) BDC $289.95
6738 2.5-10×50 Nikoplex $369.95
6739 2.5-10×50 BDC $379.95
6740 3.5-14×40 SF Nikoplex $349.95
6741 3.5-14×40 SF BDC $359.95
6742 3.5-14×40 SF (silver) BDC $369.95
6743 3.5-14×40 SF Mildot $359.95
6744 3.5-14×50 SF Nikoplex $449.95
Part # Model Reticle MSRP
6745 3.5-14×50 SF BDC $459.95
6750 3.5-14×50 SF Illuminated Nikoplex $569.95
6751 3.5-14×50 SF Illuminated BDC $579.95
6746 4.5-18×40 SF Nikoplex $449.95
6747 4.5-18×40 SF BDC $459.95
6748 4.5-18×40 SF Mildot $459.95
6749 4.5-18×40 SF Fine Crosshair with Dot $459.95
6752 4.5-18×40 SF Illuminated BDC $579.95
6753 4.5-18×40 SF Illuminated Nikoplex $569.95
For the next 20 shots, we kept “chasing center” trying to get the gun zeroed at 600 yards. We never did. After burning a lot of ammo, we gave up. Before stowing the gun for the trip home, I dialed back to my 100-yard zero, which is my normal practice (it’s 47 clicks down from 600-yard zero). I immediately noticed that the “feel” of the elevation knob didn’t seem right. Even though I was pretty much in the center of my elevation (I have a +20 MOA scope mount), the clicks felt really tight — as they do when you’re at the very limit of travel. There was a lot of resistance in the clicks and they didn’t seem to move the right amount. And it seemed that I’d have four or five clicks that were “bunched up” with a lot of resistance, and then the next click would have almost no resistance and seem to jump. It’s hard to describe, but it was like winding a spring that erratically moved from tight to very loose.
As a Father’s Day Promotion, Bushnell is offering rebates on Trophy XLT and H20 full-size binoculars and a GPS tracker for hikers/hunters. 
Ever wish you could see the image from your riflescope on a large bright screen, and record your shooting experience when shooting targets or hunting? Well, here’s a new product that offers that functionality. The 
We think this product (or something like it) will be very valuable during training. The large view-screen allows instructors to “see what the shooter sees”, so the trainer can provide immediate feedback to the trainee. In addition, while practicing at long range, a shooter can record the position of wind-flags, or record mirage for later analysis. During a match, the iScope could be used by match directors to record shot placement, with a “shooter’s eye view”.
Hunters and tactical shooters need scopes with good low-light performance. For a scope to perform well at dawn and dusk, it needs good light transmission, plus a reasonably large exit pupil to make maximum use of your eye’s light processing abilty.* And generally speaking, the bigger the front objective, the better the low-light performance, other factors being equal. Given these basic principles, how can we quickly evaluate the low-light performance of different makes and models of scopes?
*In low light, the human eye can typically dilate to 5mm – 7mm. The exact amount of dilation varies with the individual, and typically declines, with increasing age, from 7mm (at age 20) to a dark-adapted pupil of about 5.5mm by age 65. To take full advantage of a scope’s light-gathering capacity, the diameter of an eyepiece exit pupil should be no larger than the max diameter of your eye’s dark-adapted pupil, so that all of the light collected by the scope enters your eye, rather than falling on the iris. A large 8mm exit pupil may seem good, but it would be partly “wasted” on a shooter in his 60s.
Since its introduction, the big 12-42 NXS has always been one of the most popular and successful long-range and target scopes, and now you can save big bucks. 
If you want a March scope, now’s a good time to buy. Jim Kelbly of 
