Editor's Note: this really excellent comparison is entirely a brainchild of Bill, who goes by @Glassaholic here and on Sniper's Hide. I had to split it into two parts due to a character limit imposed by Locals.
Tangent Theta 5-25x56, ZCO 5-27x56, Schmidt & Bender 3-27x56, Schmidt & Bender 5-25x56, Vortex Razor G3 6-36x56, March G2 5-40x56, March 4.5-28x52 and Burris XTR III 5.5-30x56 Reviewed
PART 1
It has been almost a decade since I first began doing reviews for scopes on Snipers Hide and if you would have asked me ten years ago if I’d be doing a review of some of the highest end scopes available on the market I would have “spit out my milk” (the most expensive scope I had at the time was a Zeiss Conquest 4.5-14 with Rapid Z reticle). Like many of you, the Hide has ruined me when it comes to average grade scopes, what I used to think was “all that was needed” has become something I won’t even consider today, at least not for anything serious. I used to be an moa guy, or rather an IPHY guy, who thought mils were something that forged steel or related to the metric system or equaled centimeters and well, as an old fashioned American I don’t know no centipeders and never gave it the time of day. Similar situation with SFP vs. FFP, up until about 20 years or so ago I don’t think I could have told you what a first focal plane reticle was, weren’t all reticles the same? I could go on and on about the knowledge I’ve picked up from the Hide and diving more into the shooting sports, but you get the point, I was an ignoramus who thought he had enough knowledge to shoot long distance (at that time I thought 300 yards was long distance) and didn’t need anyone else telling me otherwise. Years ago someone took the time to patiently explain to me what I was missing and one day it finally clicked, I saw the light and realized my way of thinking with moa = inches and mil = centimeters was completely faulty, both are angular measurements and can be used successfully for solutions to hit a target at any distance (within the viable range of a given cartridge and barrel). Most of us today use mrad (mil) or moa hash reticles which is commonly referred to as the “ruler in front of you”, stop thinking about inches or centimeters – they mean nothing to the angular measurement, but instead input your DOPE into a ballistic solver, use the solution and shoot, watch for bullet impact or splash and notice that your reticle shows POI (Point Of Impact) was .8 mils below and .3 left of where your POA (Point Of Aim), you don’t have to calculate inches or centimeters at all, you just adjust your POA or move your turrets the proper direction and voila, next shot – impact, simple as that (well maybe not if it’s a very windy day). This review is not going to get into the merits of using moa or mil reticle/turrets (if you’d like to know more, click here >>> https://www.snipershide.com/precision-rifle/stop-the-debate-mils-vs-moa-vs-iphy/) but based on the scopes in my review it is clearly focused on FFP optics, which I do feel, in many ways, are superior to SFP optics especially if using any kind of milling style reticle.
HISTORY OF SCHMIDT & BENDER
Schmidt and Bender has been around since 1957 but it wasn’t until the PM II class 5-25x56 riflescope was introduced in 2005 (FFP in 2006) that things really began to take off in the precision rifle community, this scope single handedly changed the landscape of the high end FFP market and for many years was “the” scope for serious long range dynamic competition sports due to the unsurpassed (at the time) optical and mechanical quality of the scope, if there was one flaw it would be the tunneling that occurs from 5-7x which has caused many to regard this scope as a 7-25 design more than a 5-25 design.
The 5-25x56 PM II has received a facelift in 2022 in order to withstand the latest requirements of climate zone C2 (-46 degrees Celsius) or diving depths up to 25 meters. In addition, the low profile turrets are advantageous for mounting an LRF above the objective. A redesigned magnification ring is made out of solid aluminum and can accommodate a Throw Lever. In addition, the diopter adjustment can mount a military grade Polarization Filter via a thread as well as Tenebraex caps without needing any bulky adapters. Another new option is a new ocular design that is supposed to remedy the tunneling effect and make the scope a true 5-25 design.
Schmidt and Bender has been awarded the precision sniper rifle dayscope contract. These scopes will be used by special forces for the Army, Navy, Air Force, and Marine Corps.
HISTORY OF TANGENT THETA
For many years Schmidt & Bender had been known as the “premier” riflescope manufacturer in the first focal plan (FFP) world, but with the prolific uprising of PRS and other dynamic shooting sports other manufacturers began to catch on and realize there was some money to be made from this niche high end market. Maybe before anyone else recognized this, it was Chris Thomas of Premier Reticles who saw the light and had the brilliant idea of starting a Skunk Works* of sorts in the high end optical scope world - around 2007 he grabbed what some would say were some of the “best of the best” engineers from the sport optics world and founded the renowned Optronika group - for those who may be somewhat new to the game, Optronika was the brainchild behind the Premier Heritage scope line but their glory days were only short lived (as well as Premier Reticles) and soon after Premier went under Optronika became German Sport Optics (GSO) with help from Blaser and Minox, which is why the Minox ZP5 line of scopes also share the optical design of the Premier/TT lineage. During its heyday, Premier Heritage was regarded as some of the best glass out there, maybe only rivaled by Hensoldt. Around 2013/2014 ATI of Canada acquired Premier Heritage scopes and soon thereafter Tangent Theta was born, building upon one of the best optical designs in the industry, engineers at ATI went to work and created what many consider to this day to be the best turrets on the market, their distinct clicks and simple toolless zero set/stop feature are still unrivaled (though some are getting close – more on that later). As an aside, Chris Thomas went to work for Gunwerks shortly after the fall of Premier and was responsible for the Revic scope design which was another innovative product with its built in HUD; some quick internet sleuthing shows that Chris has been President of Premier Technology, a company I have not heard of so would be curious to learn more as whatever he touches tends to turn into something innovative and productive.
*The Skunk Works holds a special place in my heart as my father was hand picked by Kelly Johnson in the early 50’s and worked for them until his retirement in the early 90’s.
Editor’s Note: the development of Tangent Theta scopes started out before Armament Technologies invested into Premier. Eventually, due to a variety of problems, Premier went under and ATI, being the investor in Premier at the time, ended up with all of its assets. Optronika in Germany merged with Minox and became GSO. They currently make riflescopes under Minox and Blaser brands. Tangent Theta optical design is an evolved version of the original Premier/Optronika with very different mechanics.
HISTORY OF VORTEX
Ask someone about Vortex scopes 20 years ago and you’d get blank stares, that’s because the company was just beginning. Daniel Hamilton and his wife Margie started Eagle Optics in the mid 80’s with an emphasis on mail order sales of various sport optics, in fact, in 1998 I bought my first “high end” optic from Eagle Optics (I still have the receipt), it was a Bausch & Lomb Elite 4000 4-16x50 and had excellent glass for the time. Mr. Hamilton began Vortex in 2002 and in 20 years has become one of the worlds largest sport optics manufacturers. In 2014 Vortex announced their Gen II series of Razor HD scopes and while the 4.5-27x56 would not compete for best glass, it offered one of the best values in the growing PRS world with some putting it at the same level as the Nightforce ATACR F1 series that many considered to be cream of the crop at the time. Whether it was marketing genius or generous sponsor program or the fact they made a fantastic scope at a great price (more likely all three together), this scope went on to be one of the most used scopes within the top 100 PRS shooters for a number of years according to Precision Rifle Blogs surveys, only being topped out by Nightforce’s ATACR 7-35x56 in recent years which I’m sure contributed to the design of the latest Gen III Razor, the 6-36x56 introduced in 2022. Will the 6-36 follow in the footsteps of the 4.5-27 and lead the pack in PRS and NRL sports going forward, only time will tell but without giving too much away in my review, I would not be surprised.
Editor’s Note: the first Vortex Razor Gen2 scopes were shipped in summer of 2014, about a year before Nightforce introduced the FFP version of the ATACR 5-25x56. As far as comparative size of different companies in the sporting optics world goes, we can safely assume that Vortex is easily the largest one by revenue and it is not close.
HISTORY OF MARCH
March is another company with beginnings in the 2000’s. In 2004 Shimizu Fumio and others formed DEON Optical Corporation and in 2007 the first March scope was introduced. With a primary focus on benchrest and F Class shooting styles, March entered the FFP market in 2011 with the 3-24x42 scope, offering one of the first 8x erector FFP scopes to the market. When I joined Snipers Hide in 2012 one of my first questions related to lightweight tactical scopes and I got a plethora of answers but the two scopes that stood out were the Premier Reticles LT 3-15x50 and the March 3-24x42. Having a background in professional photography I knew a little about scope/lens design and new that the higher the magnification range (or zoom range in lens terminology) the more image quality (IQ) is degraded, memories of my first Tamron 28-200 came to mind that was quickly sold for much better quality “professional” grade lenses. So, you could say I had some hesitancy when some guy named ILya (aka Dark Lord of Optics) gave high praise to the March design and soon I would have my own and was impressed to say the least, but one of my goals was low light capability and ultimately the darkness of the 42mm objective had me looking elsewhere. Soon thereafter the 3-24x52 was released and I picked that scope up as well and was pleasantly surprised at how well this scope performed, but at the time I was obsessed with the Christmas tree reticle craze and ultimately moved on. Back in 2018 March was struggling with getting a better foothold into the FFP market and specifically the PRS/NRL style sports, their 3-24x52 and 5-40x56 scopes were decent sellers but not making many waves in these sporting competitions and their reticles were rather uncompelling to this market as well. Through an interesting set of circumstances, I was put in touch with March leadership where I gave my honest opinion and advise on the current lineup and potential future designs, I also put March in touch with ILya who was the brain behind the excellent FML-TR1 reticle and soon March had input from some PRS competitors to create the FML-PDK reticle. A short body scope with too much magnification just has too many limitations for dynamic shooting sports, terms like “narrow depth of field (DOF)”, “finicky eyebox and parallax” seemed to come up often when 8x erector scopes were mentioned. March took the constructive criticism to heart and soon thereafter the 4.5-28x52 was born, a first for March with a 6.22x erector and some other secret sauce to help this scope perform amazingly well for such a short body design.
Editor’s Note: The original team at Deon came out of Light Optics Works. They started their company in order to produce the best that could be built in Japan. They are really adept at keeping very high performing optical systems comparatively light and exceedingly durable.
HISTORY OF ZCO
Around 2018 (or just before) a brand new scope company was introduced to us and the official announcement may have come first right here on the Hide, I remember seeing that thread for maybe a week or so before I actually clicked on it, and I’m so glad I did because unbeknownst to me ZCO would become synonymous with “zero compromise” and would soon be discussed in the ranks of TT, Schmidt and Hensoldt. Many years ago Jeff Huber was a big part of a little company some of you may have heard of called Nightforce and after a bitter departure with Nightforce found himself as the marketing guru for Kahles USA and I assume was responsible for the relationship with Shannon Kay of K&M Shooting Complex that was a big part of the birth of PRS shooting competitions. I remember this well because it was around 2014 that I was in the market for a higher end scope, but was very particular about reticles and the SKMR series of reticles had just been released with the Gen III version of the venerable Kahles K624i, and I had a long talk with Jeff on the phone which ultimately convinced me to spend the extra money to go this route. Jeff then left Kahles and we soon found out why when Zero Compromise Optic was introduced – optics that are assembled right here in the USA with parts manufactured in their uber secret facility in Austria. Combining one of the best ergonomic designs in the market along with stellar Austrian glass, ZCO has taken the competition world by storm.
Editor’s Note: The origins of ZCO are not entirely clear, but the core team both in US and Austria all came out of Kahles. In some ways, ZCO scopes are what Kahles should have been. I do not have any insight into whether they were pushed out of Kahles or left because the product direction they wanted wasn't happening at Kahles or if it was a simple management dispute. Whatever the cause, ZCO has clearly made an impact on precision shooting community.
THE SCOPES
Tangent Theta 5-25x56, ZCO 5-27x56, Schmidt & Bender 3-27x56, Schmidt & Bender 5-25x56, Vortex Razor G3 6-36x56, March Gen2 5-40x56, March 4.5-28x52 and Burris XTR III 5.5-30x56
Why only these, how come brand X or model Y aren’t in here, well plain and simple I am limited on funds and I have to purchase most of the scopes for my reviews, so I’m limited to my own personal collection as well as what may interest me at the time so I do apologize if a scope you were really hoping would be included is not in here, maybe a possibility for a future review… Yes, in some of the images you see the Burris XTR III 5.5-30x56, mostly because it was my rimfire trainer scope prior to this review and I was curious how a $1k class scope would compare to the alpha class which cost a considerable amount more.
A couple years ago I reviewed the March 4.5-28 alongside the Tangent Theta 5-25, not because I thought it would be a “fair” comparison but out of curiosity to see how well the March could hold against what many consider to be one of the best scopes on the market today. I also had the March with my ZCO 4-20 and am providing those two images below to give you an idea of the size comparison, what is unique with the March is that it is the only “ultra short” scope out of all these reviewed here which does put it at somewhat of a disadvantage (short focal length scopes with high magnification erectors tend to be more finicky with eyebox, DOF and Parallax).
Keep in mind this evaluation is based on my own personal observations based on what my eyes “see” when looking through the scope. I pay meticulous attention when setting up my diopters for each scope making sure to fine tune them to my eye. My eyes are very sensitive to CA while some people cannot or have difficulty seeing CA when looking through the same scope. Everyone’s eyes are different, and my observations will undoubtedly be different from others. That being said, I try to be as objective as possible but, like all of us, do have my bias’, though I try my best to inform you of my own personal preferences so you can make judgement calls based on your own preference. It should also be noted that I am not paid by anyone to do these reviews, I do have some relationships with dealers and some manufacturers that help out some, but by no means am beholden to any particular manufacturer and those that I do work with are well aware of this. Special thanks go out to Mountic Oudtoors @MOUNTIC (https://mounticoutdoors.com/) who is a Hide sponsor and dealer in Tangent Theta, ZCO, March, Manners, Spuhr and more, I’d also like to thank Jason at eurooptic.com with the Schmidt 3-27.
SPECS
The below specs are provided by the manufacturers which provides a good baseline for what these scopes offer. Vortex is highlighted in yellow as it is new for 2022. Highlighted in red is a potential drawback and in green is a potential benefit.
TURRETS
This review does not cover the accuracy of each scope but covers the functionality – since any manufacturer is capable of producing a lemon it’s always a good idea to test your scope to ensure its mechanical accuracy.
Tangent Theta
I wrote the following in my previous review and will repeat it here - I have never considered myself a turret purest, having had many other scopes by numerous manufacturers over the years I could never quite understand what the “fuss” was all about with regard to turret feel. My general rule is – can it get me where I want to go quickly? If the turret can do that and is repeatable then it is a win in my book. That being said, I have experienced some somewhat lackluster turrets that leave much to be desired, so I assume we all have a threshold we are willing to accept. All that being said, if turret feel is your game, then Tangent Theta owns it – very distinct, no play whatsoever and a nice clunk between each .1 mrad gives you a sense of confidence anytime you spin the elevation or windage. Keep in mind these are 15 mrad per rev, and sometimes the spacing can be too tight when mfr’s try to pack so many clicks into one rev, but TT decided to give you something more akin to a Ferrari stick shift to grab onto – it is meaty and with a diameter that allows for refined spacing throughout the 15 mrad of travel for each rev. Another unique feature is the toolless zero, something else that is unmatched in the industry. Have you ever found yourself at the range and forgot that tiny little hex wrench? What usually follows is #@&^%#$. With the Tangent you simply use your fingers to loosen the top plate of either elevation or windage and then you pull up slightly and spin to wherever zero is, push back down and tighten the top plate, that’s it, no hex wrenches needed. The Zero stop is always .5 mrad under 0 so this is automatically set wherever you set zero. Something I wish every manufacturer would introduce and if you don’t have that feature then do what Kahles did and stick a magnetic hex wrench inside the illumination battery cover so you have easy access in the field. My one and only complaint is that for such a massive turret housing, TT opted to put little tiny numbers, for young eyes this may not be a big deal, but ZCO got this one right with their large numbers and bold lines, something I wish TT and others would offer. Having had several Tangents now I can say they still reign supreme but that mountain is being climbed by other manufacturers (see below) that some may consider just as good if not better than TT. Turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions.
March FFP Gen II 5-40 turrets
Having reviewed the March 5-42x56 HM a couple years ago I fell in love with those turrets, not just for their locking mechanism but for the superb feel that is one of the closest to Tangent Theta I have felt to date. March has essentially put the same turrets in the 5-40 scope and labeled it “Gen II”, like the 5-42 turrets before, these turrets excel with extremely positive clicks and nice wide 10 mrad per rev spacing, even if you do not need the locking mechanism, these turrets are a refinement over March’s standard turrets that is hard to describe – it is a very distinct click with excellent audible feedback. The locking mechanism is unique and sits atop the turret as a lever that you can switch on to lock or switch off to allow it to freely spin, both elevation and windage share this design which is an advantage. I prefer this (and Schmidt’s DT II+) design over the up/down mechanism of the Vortex and ZCO. To set the zero stop there is a small hex nut at the top of the turret that you tighten but be careful not to over torque, my only gripe is that if you don’t tighten far enough it is easy to move past the zero desired which may limit its repeatability. Turrets are translating which means the turret rises and lowers when spinning through the different revolutions.
Editor's Note: I have spent a TON of time with March's new turrets and with S&B's DTII+ turrets. These are easily my favourite locking turrets on the market at the moment. I thought they would lock up after a few months in unhospitable environments out here, but they gave me zero issues.
Schmidt PM II 5-25 DT turrets
These represent some of the traditional turrets that Schmidt has offered for a while, they are somewhat muted and close together, but no noticeable play between clicks. Setting your zero is done through traditional hex screws on the periphery of the turret. Turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions.
Editor's Note: These have been around for a very long time and they work well. Their durability has stood the test of time, but if I were buying a S&B scope, it would have the DT II+ turrets.
Schmidt PM II 3-27 DT II+ turrets
These turrets are completely different from the traditional design Schmidt has offered in the past, they are somewhat lower profiled and a bit larger in diameter, but the main difference is in how they function. These turrets have a very solid and distinct click value with minimal play between clicks – Schmidt engineers did their homework on this one. Turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions. The added benefit of the DT II+ system is you have a lever for both elevation and windage that allows 3 settings: Locked, Unlocked with MTC and Unlocked without MTC (for those who may not know, MTC stands for More Tactile Clicks which means every full mrad value the click is stiffer than the rest providing a “more tactile” response). When in the locked position there is no play or movement in the turret. It should be noted that I had issue with previous generation MTC turrets, the full mil stronger click was so strong it would cause me to inadvertently overtravel by .1-.2 clicks coming out or going back (for example: if I had a solution of 5.1 mils I would overtravel to 5.2 or 5.3 and would then have to dial back causing delay) the DT II+ MTC has rectified that and feels like the ideal resistance without having to jump forward to get out of the full mrad value. The Schmidt turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions. I would rate these turrets as the best yet from Schmidt and Bender and arguably close to Tangent Theta in quality.
Editor's Note: DTII+ turrets are on the left in the picture above.
ZCO 5-27 turrets
ZCO offers a double bearing design that is supposed to provide more even clicks throughout the travel. The clicks are slightly muted, a little mushy with slight play but very accurate. ZCO offers a locking mechanism where you have to pull up on the turret to unlock and spin and then push down to lock. Recently ZCO has offered a non-locking design called NLE (Non-Locking Elevation) which is preferred by some. Turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions. Overall the turrets are very nice but not at the level of TT, Schmidt DT II+ or March (from this review).
March FFP 4.5-28 High Master turrets
Having owned some March scopes previously, I had an expectation the turrets would be about on par with that experience; however, I have been pleasantly surprised with the latest turrets from March as they have very little play and very distinct clicks. An interesting feature that March has had for a number of years is the 0-Set (or Zero Stop) which is “almost” toolless – if you have a coin or a key in your pocket you should be able to turn the 0-Set to define your zero stop after you have reset zero which does take a 1.5mm hex key. While it’s not toolless, and it’s not like Kahles with the key hidden in the illumination cover, March does give you a little key chain sized hex tool that doesn’t take up too much room on the key chain. The zero stop is a friction design and can have overtravel if you twist hard enough, but most of the time will fall on where you’ve set it. The windage does come capped on the 4.5-28; however, it does have a nice feel so those who prefer to dial for wind can simply remove the cover to have a nice exposed windage turret that is still big enough to grab and spin even if gloved. Turrets are translating which means the turret rises and lowers when spinning through the different revolutions. Something else unique to the 4.5-28 scope is that March is providing a larger diameter turret shroud that can be bolted onto the fixed housing, I do prefer the larger numbers and diameter but because the turrets are translating I’ve found it makes it a little harder to determine center unless you are completely centered behind the scope.
Vortex Razor HD Gen III 6-36x56 turrets
The Razor Gen III represents the top of the line scope from the vast array of scopes that Vortex offers to the public. Similar to ZCO, Vortex offers a locking mechanism that must be lifted up to unlock and spin and then pushed back down to lock. There have been a number of complaints from the community on the inconsistency with turret function and feel between scopes, something it would seem Vortex is trying to rectify through their stellar warranty program; however, even after servicing - my turrets are still pretty muted, a bit mushy and with a slight bit of play, but they do manage to fall on the appropriate hashmark each time. These turrets will probably not win any awards, but they do get the job done which is what matters most. Turrets are non-translating which means the turret does not rise or fall when spinning through the different revolutions.
Burris XTR III 5.5-30x56
Resistance is a bit tight on the USA model I had for this review, that along with the sharp knurling can make for a somewhat uncomfortable experience when spinning these turrets. They do have a good sound and there is slight play in between clicks. Turrets are translating which means the turret rises or falls when spinning through the different revolutions.
Editor’s Note: Burris does have an improved version of this scope out called the XTR Pro. It sports improved image quality and reticle illumination along with a few additional tweaks. It would be a stronger competitor in this group had it been out a bit earlier.
Turret Mechanical Assessment criteria (ratings: = (equals) > (greater than) ranked highest to lowest):
Turret Click Spacing Ranking:
March G2 5-40 >= TT = SB DT II+ > March 4.5-28 >= ZCO > Burris XTR III > SB DT > Vortex G3
My rankings for turret click spacing have to do with both the distance between clicks and the resistance between those clicks. This is more or less a personal preference, but my hand feels better with wider spacing and good resistance but not too much.
Turret Click Feel Ranking:
TT = SB DT II+ = March G2 5-40 > March 4.5-28 >= ZCO > Burris XTR III > SB DT = Vortex G3
This can be very subjective, but I am drawn to more distinct click feel and audible feedback with very little play between marks.
Turret Alignment Ranking:
TT = SB DT II+ = SB DT > ZCO = Vortex G3 > March G2 5-40 = March 4.5-28 > Burris XTR III
I define turret alignment by the ability for the turret hash marks to fall directly on the indicator mark and not being offset while running the turret out to the extreme and back. Because of the nature of translating designs, they do rise pretty high above the center mark which gives a slight perception you are off mark if your eye is not perfectly centered. I much prefer the non-translating designs that do not rise and fall so preference is given for these designs.
Turret Reset Zero and Zero Stop Ranking:
TT >> March 4.5-28 > March G2 5-40 > Vortex G3 > SB DT II+ = SB DT = ZCO = Burris XTR III
In order to reset zero on the March, Schmidt, ZCO and Burris scopes you have to loosen the side hex bolts on the turret housing, then spin the turret to align zero and re-tighten, this is typical of most long range scopes today (zero stop on S&B is around 0.6 mrad below, ZCO is 0.5 mrad below and I can’t remember with the Burris and have since sold the scope) and is only bested by the toolless design of the Tangent Theta turrets. March offers the coin/key adjustable zero stop mechanism on the 4.5-28 and a hex key adjustment on the G2 5-40; however, some may find an issue as this feature does not always stop below zero at the same spot – depending on how much torque you give it (with your fingers) you may stop short or overtravel from where you intended to set the actual stop. Tangent is always fixed at .5 mrad below zero and that is something you can count on every single time which has its advantages for night shooters and those who prefer to count up after hitting the stop vs. visual recognition. Vortex is unique in that the Razor G3 turrets are zeroed by loosening one hex head screw and then turning the center of the turret, there aren’t clicks when turning the center of the turret so you can set it exactly where you want for a precise zero (zero stop is always 0.5 mrad below zero), you can even mark the center dial for switch barrel platforms to easily change zero between barrels.
Total Travel Adjustment (Elevation) Ranking:
Vortex G3 36.1 mrad > ZCO 35 mrad > SB DT II+ 34 mrad > March 4.5-28 30 mrad > TT 28 mrad > SB DT 26 mrad = Burris 26 mrad > March G2 5-40 24 mrad
Pretty self explanatory. There is variation of windage adjustment but as I almost exclusively hold wind with the reticle, this does not play a factor for me and therefore is not evaluated (however, the spec sheet above shows the exact amount for each scope for those who are interested).
Turret Locking Mechanism Ranking:
Schmidt DT II+ >= March G2 5-40 > ZCO > Vortex G3 > Burris – NA = March 4.5-28 – NA = Schmidt DT – NA = TT – NA
Some of these scopes do not offer a locking mechanism so I am going to rank them NA (Not Available). The Schmidt DT II+ and March G2 5-40 locking mechanism is the best I’ve seen as they allow you to turn the locking feature on or off with a mechanical lever separate from the turret housing itself; whereas, the locking mechanism of the ZCO and Vortex G3 are the pull up to unlock and push down the turret to lock, this method can “fall” into lock depending on how you spin the turrets, of these two the ZCO feels to be more distinct and possibly has less ability to “slip” vs. the Vortex.
Overall Turret Mechanical Assessment Ranking:
TT >= Schmidt DT II+ >= March G2 5-40 > March 4.5-28 >= ZCO > Burris >= Vortex G3
A few years ago, Tangent Theta was simply the best of the best with regard to feel and function; however, I would say the S&B DT II+ and March Gen2 locking mechanism are encroaching on TT territory. I’d like to reiterate that my rankings are biased towards features, feel and functionality that I prefer so please keep this in mind – where I prefer more distinct sounding clicks you may prefer more muted clicks and would therefore rank other scopes in almost the opposite order in which I have.
MECHANICAL ASSESSMENT OF MOVING PARTS
Besides the turrets you have other moving parts on a scope: the magnification ring, the parallax adjustment and an illumination module, which all require some type of adjustment. Sometimes manufacturers make the resistance too hard or too light. These parts are evaluated based on “resistance” which allows them to turn freely with two fingers, but not so loose that they could get bumped out of position accidentally. In addition, if resistance is so high that turning a dial would cause POA to shift - this would be considered a negative.
Mag Ring, Parallax, Diopter and Illumination Mechanical Assessment criteria (ratings: = (equals) > (greater than) ranked highest to lowest):
Magnification Ring Movement Ranking:
Vortex G3 >= Schmidt 3-27 = Schmidt 5-25 > TT >= ZCO > March 4.5-28 >= March 5-40 > Burris XTR III
The ideal magnification ring resistance (IMHO) is one that can easily be turned with two fingers – not so hard to turn as it may now affect your POA and not so light that a brush of your hand (or light bump into a barricade, branch, etc.) is going to change the setting. The Vortex G3 had what I consider to be the best with regard to resistance and smoothness. Next up would be the S&B 3-27 and 5-25 which both exhibited excellent resistance and smoothness. The TT was slightly stiff but very smooth while the ZCO might have been ranked higher as it had outstanding resistance, but it felt a little “gritty” when turning. Both March scopes were a little too stiff to be ranked higher, but not bad and very smooth. The worst of the bunch was the Burris XTR III, the magnification ring needs a pipe wrench to turn and worse yet I sent this scope back to Burris for “repair” and Burris kindly looked at it and wrote back saying it is within spec – not sure what gorilla’s work at Burris and think 200 ft-lbs of torque is good spec for a scope but that’s a complete no go in my book, in defense many shooters will say “get a Throw Lever” and while this does definitely help, I think a scope should be both usable with and without a mechanical helper.
Parallax knob Movement Ranking:
ZCO >= March 4.5-28 >= March 5-40 = Schmidt 3-27 = Schmidt 5-25 > Vortex G3 >= Tangent Theta > Burris XTR III
The parallax on the ZCO, both March scopes and both Schmidt scopes were all outstanding offering what I’d consider the right amount of resistance while being very smooth. The resistance on the Vortex was very tight, so much so I thought I’d check how good the Vortex VIP warranty is and sent the scope in and was pleasantly surprised they were able to lighten it up to maybe a little better than TT level which is to say “excellent” – completely different experience from Burris warranty with the magnification ring where they did nothing. The Tangent has more resistance than the magnification and takes some force to turn, I would not say the force is too much, but rather more than I would prefer, but coming up last again is the Burris XTR III with having a bit too tight of resistance.
Parallax Adjustment Forgiveness:
ZCO >= TT >= Vortex G3 > March 4.5-28 >= Schmidt 5-25 > March 5-40 > Schmidt 3-27 > Burris XTR III
What exactly is parallax “forgiveness”? I define this as how finicky it is to adjust the parallax dial in order to get parallax properly set for the distance to target from the scope, keep in mind that many think of the parallax dial as more of a “side focus” and indeed it does help focus the image but it’s primary purpose is to correct for parallax misalignment which can cause you to miss a target at distance. ZCO, Tangent Theta and the Vortex G3 really stood out among the rest to be some of the most forgiving which is not a huge surprise with how long these scopes are with relatively mild erectors (5.4x, 5x and 6x respectively). The next surprise for me was the March 4.5-28 which is the shortest scope of the bunch and short scopes tend to struggle more than long scopes, the March comes up very close to the Schmidt 5-25, following that was the March 5-40 with an 8x erector, the Schmidt 3-27 with it’s 9x erector was definitely more finicky and the Burris XTR III was also pretty finicky.
Editor’s Note: Side focus knob is indeed image focus. That is its primary function and when the scope is set up correctly, while focusing the image it also dials out parallax error. Perhaps, I need to re-visit this topic in more detail.
Diopter Adjustment Rankings: Tie
All scopes tested here offer a “fast focus” diopter allowing for quick adjustments, some offer a lock ring to help against slippage but it’s wise to use some kind of semi-permanent marker to mark the ideal setting for your eye. If you have not seen my PSA on setting up your diopter, it is attached, so you can look at the process to better set your diopter for your eyes (if you are used to the blank wall or blue sky method only you may be missing out on maximum performance of your scope).
Editor’s Note: it is a very good PSA, but somewhat incomplete. I am pretty sure I have covered it in a livestream, but it is another topic that should be re-visited.
Illumination Dial Performance Rankings:
ZCO > Vortex G3 >= Schmidt 5-25 and 3-27 >= Tangent Theta > March 4.5-28 and 5-40 > Burris XTR III
There is no question that ZCO offers the widest range of features with illumination – you have the ability to select between red and green, there is an auto on/off feature that knows when the scope is slung on your back and will not activate until it gets in a position to fire. Vortex offers a locking feature on illumination and it must be pulled out to turn. There seems to be a love or hate relationship with Schmidt and Bender’s illumination tumor, but the rheostat function is very smooth. Tangent Theta uses a dial with on/off positions as you rotate from lowest to highest power settings, there is definitely more real estate to grab and turn on the TT which gives it an advantage. March is using a rubber cover over a push button for on/off functionality with numbers 1-6 on the side of the dial, due to being on the side it can be difficult to turn especially if wearing gloves. March also has an automatic shutoff after one hour from being turned on which will help save battery (I have often left illumination on and forgot to turn off only to find my next outing there is a dead battery). Burris XTR III has no illumination (the new XTR IIIi does).
Illumination Daylight Bright, Coverage and Bleed:
ZCO >= Vortex G3 > Schmidt 3-27 > TT >= March 4.5-28 = March 5-40 > Schmidt 5-25 > Burris XTR III
ZCO has one of the brightest reticles on the market and is what I consider to be daylight bright (keep in mind I’m not talking Aimpoint or other RDS bright) for a long-range scope which is to say it can be seen in bright midday sun, the entire reticle lights up and there is no discernable bleed even at highest brightness in low light. Next runner up is the Vortex G3 also with a daylight bright reticle, but different from ZCO Vortex has opted to only illuminate the main vertical and horizontal stadia lines, only minimal bleed was noticed at highest brightness in low light. The Schmidt 3-27 comes in next and was ever so faint in daylight and barely visible in shadow, only center cross lit up and bleed was minimal. The next scopes were harder to ascertain ranking as none of them were daylight bright by any stretch of the imagination, the TT had good illumination quality with no bleed and center cross is illuminated with some dots in the tree as well. Next was the March 4.5-28 which only illuminates a very small center cross and dot, no bleed is noticeable and very good low light performance. The March 5-40 is similar to the TT in that the full cross is illuminated along with some dots in the tree, no bleed was noticed and coming in last was the “old” Schmidt 5-25 which has very dim illumination even at highest settings but because of this no bleed was noticed, this would be a low light illumination use only. The Burris XTR III of course has no illumination but user reports say the new XTR IIIi has a very dim illumination module that is not usable in daylight which is unfortunate as it’s sibling the XTR Pro is supposed to have a daylight bright illumination module – must be one of the perks you get when you go “Pro”.
Editor’s Note: ZCO’s illumination is superb. The only precision scope that is as good is the new Zeiss LRP S5.
Overall Mag Ring, Parallax, Diopter and Illumination Mechanical Assessment Rankings:
ZCO > Vortex G3 > TT >= March 4.5-28 = March 5-40 > Schmidt 3-27 > Schmidt 5-25 > Burris XTR III
When including everything above, it’s pretty clear the ZCO wins this one hands down as it offers pretty much excellence across the board with the only deficit being the “gritty” magnification experience. The rest of the pack I’m going to rank based on my first impressions of the whole mechanical experience and not necessarily with an average of the order above. Again, take my rankings with a grain of salt because they are based on “my” preferences for the most part. One thing is clear, Burris comes in last and I suppose based on its price point this should not be a surprise; however, it is my understanding that the new XTR IIIi scope offers improvements over the original XTR III with regard to mechanical function and considering it’s “above class” optical performance, makes it a very compelling option for those on a budget.
For the rest of the article and the conclusions, see the next post: https://darklordofoptics.locals.com/post/3076493/alpha-class-long-range-scope-review-part-2
Editor's Note: I did not want to pollute the whole thing with affiliate links. Most of these are available from Eurooptics and a few other fine retailers https://bit.ly/3tYC193