Location: United States
I cut and pasted this from another forum..
" At the end of the main article, I also included the three sections that are boxed in the article, the picture captions and the tables.
If the pain calls. Whoever wants to shoot successfully at 200 and more meters, cannot get away from the acquisition of a high-quality long range sight. VISOR tested therefore nine optics from eight manufacturers in the middle to highest price range.
While the German and Russian snipers of WWII used 3.5 to 4X scopes, Unertl had introduced optics of up to 8X. Until 2005, the 10X magnification of the M24 and M40 had remained the top optics in the US Army. But times change and with new calibers and usage scenarios as well as increased ranges, more powerful optics have become the norm.
On the civilian side, there are many eager 300 meter shooters and visor testers for whom the use of sights with up to 25 power will be something they can appreciate and from which they will extract the last millimeter of precision, (from one of the test rifles.) At such distances, precision depends on the manufacturing process as well as the quality of the individual components. Visor has tested 9 riflescopes ranging from the medium price range (Nikon) to the most expensive (Zeiss) in the labs of riflescope manufacturer Schmidt & Bender of Bierbertaler, under the watchful eyes of this editor.
It’s about light: Beside the contrast and the image definition, the transmission (also called degree of light penetration) is one of the most important qualities for a high-performance optics. However the effects of small, proportional differences are in practice of a rather theoretical nature, because a difference of three to five per cent is really only seen by a trained eye, and then only under laboratory conditions and while doing direct comparisons. During our transmission measurement the difference was on the smallest side, with the reticle as far as possible to one side and down, so that the ray of light in the spectrometer (the daylight range is from about 370 to 780 nanometers) had clear path. With aligning in the "black box" the sight was rotated bit by bit, until one found the maximum value on the screen of the computer. Only then the program runs off the nanometer curve in increments of five and afterwards produces the curve, from which one can measure the maximum and the average value for daytime transmission and nighttime transmission.
"The maximum value of the curve will always be found within the brighter daylight range", explains Ingo Opitz, director responsible for quality assurance at Schmidt & Bender. This daylight range is with 500 to 650 Nm, with the majority reaching their optimum at 550 Nm. The Swarovski has a somewhat shifted optimum, at 600 and Nightforce it is even more shifted compared with the others: 650 Nm. With the Burris a small wavy course in the curve suggested, which was remarkable, that "the optics or the lens coatings was not perfectly coordinated with one another for the test sample." From the path of the curve one can judge the value of the applications. For a single coating of the lens a smooth path of the curve is typical. Multiple applications however exhibit maximum values with two different wavelengths. "With night-capable optics the transmission should be about 450 nanometers therefore still over 90 per cent", so the specialist. That results in then inevitably in dual peaks of the curve
The Impact of impact: Even if sport optics do not have to necessarily be military-hardened, they should be able to handle the impact of hundreds of rounds without problem. The firing or impact resistance tests are done on the scopes before they are mounted on the collimator. Four taps with a rubber hammer - on the objective lens, on the adjustment mechanism, on the right of and down on the main tube. Manufacturers allow a deviation of a centimeter at elevation and windage, but even at twice that, this is probably ignored when considering marksmanship or ammunition variation.
An annoyance is the click adjustment, which is not uniformly standardized world-wide. Thus the adjustment measure per clicks varies with the test candidates between 3.75 and 10 mm at 100 m. thereby one must still decide between a design with high-speed (target?) reticle adjustments (on the professional devices) or conventional adjustments, hidden under protective caps,. The cheapest scope in the test - the Nikon monarch 6.5-20 x 44 AO for 669 Euros - even brings along free high-speed (target?) adjustment knobs. We were best pleased with the clearly perceptible click stop adjustments when using the Leupold. In contrast to that the Docter was pulled down by its quiet clicks, which must be also made with a coin like Anno Tobak, with a screwdriver.
In this connection also the main tube diameter may not remain uncommented: If someone wants to go stay with the capabilities of 338 Lapua Magnum and 50 BMG (12.7 x 99 mm), he must before long quickly push the envelope of the test models to find one that is adequate. It is clear that a regular-size main tube cannot supply an adjustment range of over a meter. Thus the professional devices of Zeiss as well as Schmidt & Bender have a 34mm tube or larger, and even the Nightforce brings it with only 30 mm in diameter for the maximum adjustment of +/- to 140 cm. The only way for the 25.4mm sights to do this is by the employment of a canted scope rail.
With parallax adjustment there are two designs - in front of the objective, the other one in on the side of the main tube in a third knob. The latter offers advantages to the sniper, since it has adjustment with the target in the view and it can be used from position. With the adjustment at the objective one must look away from the target - for sporting purposes with the fixed ranges of fire, this represents no genuine dilemma. Swarovski even differentiates between meters and yards at the objective, with Nightforce and Leupold however unfortunately the desirable third tower comes without a scale - focusing becomes a guessing game.
Seal & truth: All samples of this price class are supposedly waterproof and tight. They had to begin the test however, with a one hour water bath, which took place at a depth of one meter. They passed it - with one exception: the Burris had earlier had its parallax adjustment come apart, after the tiny set screw was broken. The consequence of this for the sample was that after one hour the American challenger was declared "land under", since the eyepiece was filled with water to approximately one fifth. As a member of the Beretta group explained - that importer Manfred Albert explaining in addition: "I would like to address your concerns with the tested Burris sight 6-24 x 44 a model, that is not yet available in Germany." VISOR procured itself the sight directly from America. Manfred Albert: "the test performed is therefore not necessarily relevant to the German market; in particular, the sight did not go through the quality inspection of the German import firm."
On top of that, the image could no longer be focused properly at the different distances because of the defective parallax adjustment. Clearly that along with other tests likes the diopter setting and the focal point deviation when it is determined that the reticle is no longer in the second image plane could not be done. There w