Comparison BSA Air Rifle 4x32 vs Gamo 4X32 WR

The offset is the distance between the eyepiece lens and the exit pupil of an optical instrument (see "Exit Pupil Diameter"). Optimum image quality is achieved when the exit pupil is projected directly into the observer's eye; so from a practical point of view, offset is the distance from the eye to the eyepiece lens that provides the best visibility and does not darken the edges (vignetting). A large offset is especially important if the sight is planned to be used simultaneously with glasses — after all, in such cases it is not possible to bring the eyepiece close to the eye, and it must be at some distance from the glasses so as not to hit the glass due to recoil.

The diameter of the area visible through the sight from a distance of 100 m — in other words, the largest distance between two points at which they can be seen simultaneously from this distance. It is also called "linear field of view". This indicator is more convenient for many users than the angular field of view (the angle between the lines connecting the lens and the extreme points of the visible image) — it very clearly describes the capabilities of the device.

In sights with magnification adjustment (see above), both the entire range of width — from maximum to minimum — or only one value of this parameter can be indicated. In the latter case, the largest width of the field of view is usually taken, at the minimum magnification.

The possibility of manual adjustment of the sight from parallax, by the user himself. For this purpose, the design provides a corresponding regulator.

Parallax in this case is a phenomenon when, when the eye deviates from the optical axis of the sight (from the center of the eyepiece), the aiming mark visible to the shooter also shifts, while the sight itself remains motionless. As a result, if the eye is not exactly in the center, the visible position of the mark does not coincide with the actual aiming point. This phenomenon is especially pronounced in optical sights (see "Type"), and many collimators are also subject to it, although not to the same extent (but "night vision" and thermal imagers are free of this drawback, since the mark is displayed on the built-in display).

To eliminate this phenomenon, a specific adjustment is used - parallax adjustment. It is usually done right at the factory. However, the sight can be adjusted from parallax only for a certain distance, and with significant deviations from this distance (more than 30% downwards or 60% upwards), this effect begins to manifest itself again. It can be compensated for by an ideal insert ("eye strictly in the center"), but even for experienced shooters this can be difficult, especially when shooting standing, offhand and in other uncomfortable positions. In light of this, some models also provide manual parallax adjustment - a regulator that allows...you to set the adjustment distance at the user's discretion. In addition to the situations described above, this function will be especially useful for novice users, as well as for high-precision shooting at long distances.

Optical sights with parallax adjustment> can be equipped with a wide ring on the AO (Adjustable Objective) lens or a drum on the SF (Side Focusing) control unit, on which additional accessories for fine-tuning the focus in the form of wheels are installed.

A type of coating used in scope lenses. Anyway, we are talking about the so-called antireflection coating, which is the thinnest film (single or multilayer) on the surface of the lens in contact with air. The properties of this film are chosen in such a way as to minimize the reflection of light from the glass surface. The meaning of this function is not so much to reduce the brightness of glare that can unmask the shooter, but to increase the light transmission of the optics and, accordingly, the quality of the image visible through it.

Modern sights can be equipped with the following types of coatings:

— Illuminating. In this case, the simplest option is implied — an incomplete single-layer coating. The term "incomplete" means that not all lens surfaces are coated (although there may be several coated surfaces). Such enlightenment is inexpensive, however, the image quality is relatively low — in particular, because a single-layer film is most effective only for a part of the visible colour spectrum.

— Full illumination. Fully coated means that all surfaces of the lenses that come into contact with air have a special coating; in this case it is single layer. Such a coating is more expensive than a simple anti-reflective coating, but the quality of the “picture” when using it is higher, because. light distortion at the transitions between glass and air is minimized.

— Multi-layered illuminating. Incomplete AR coating (see above)...using multilayer films. Thanks to multiple layers, the anti-reflective coating covers the entire visible spectrum, which allows you to achieve a brighter image with less colour distortion compared to single-layer coatings; However the price of such devices is higher.

— Full multilayer enlightenment. The most advanced option: multilayer coating on all lens surfaces used in the design of the sight. Features of full and multi-layer coating are described separately above. Here we note that their combination is typical for high-class sights, because. it provides the highest quality image, but it is not cheap.

The location of the reticle in the optical sight (see "Type").

Such a grid can be installed either in the first focal plane, FFP(roughly speaking, in the lens area), or in the second, SFP(in the eyepiece area). At the same time, for sights with a fixed magnification, the difference between these options is only in price, so they use only the simpler and cheaper SFP. But in models with multiplicity adjustment, this parameter directly affects the application features, and we will analyze this difference in more detail:

— In the 1st focal plane (FFP). The key advantage of reticles in the first focal plane is that their apparent size also changes in direct proportion with a change in magnification. In fact, this means that the angular dimensions of the individual mesh elements remain the same regardless of the set magnification. That is, for example, if a distance of 1 MRAD is claimed between two neighboring points, then it will be 1 MRAD in the entire range of multiplicity adjustment. This means that you can work with the grid for measuring distances and taking corrections according to the same rules, regardless of the selected degree of increase. Thus, FFP sights are much more convenient and easier to use than SFP. On the other hand, such models are noticeably more complex and expensive; and many hunting reticles — for example, a duplex or a classic cross (see "Reticle Type") — it...makes no sense at all to install in the first focal plane. In light of all this, this option is relatively rare and only in mid-range and top-level models designed for high-precision shooting.

— In the 2nd focal plane (SFP). The most common reticle placement option, including variable magnification sights. Such popularity is primarily due to the simplicity of design and low cost. However, the reverse side of these advantages are additional difficulties when using goniometric mesh elements. The fact is that in SFP sights, the apparent size of such elements remains unchanged when the magnification changes, which means that the dimensions of individual parts at different magnifications will correspond to different angles. More precisely, the angular dimensions in such systems change in inverse proportion to the multiplicity: for example, if at a multiplicity of 5x the distance between two adjacent points is 6 MOA, then at 15x it will decrease to 2 MOA. Thus, the “true” angular size indicated in the characteristics, the marking elements have only at a strictly defined multiplicity, in other cases, this size must be recalculated using special formulas. At the same time, it is worth noting that if the grid does not have special goniometric elements, then this disadvantage becomes practically irrelevant for it; examples are hunting nets of the "half-cross" type (traditional, not "stump") and "cross with a circle" (see "Net type").

— Dust-, water protection. Protected housing that prevents dust and moisture from entering the delicate components of the sight. This feature is highly desirable if the sight is planned to be used in adverse conditions — for example, during a long hunting trip, where there is a chance of encountering bad weather. However it is worth considering that the specific degree of protection may be different, it should be clarified according to the documentation for the sight. However, almost all “protected” models are able to endure rain at least without problems.

— Impact protection. Special protection that prevents damage to the sight during impacts and shocks — for example, by accidental falling or contact with a foreign object. The effectiveness of this protection may vary for different models, but in most cases it at least allows you to transfer the fall onto a hard surface from a height of 1 – 1.5 m. with a high probability it will turn out to be useless — the impact force will be much greater than that for which the device was originally designed. In addition, after any strong impact, the sight will have to be re-aligned. However, additional protection anyway improves the overall strength and reliability of the device.

— Filling with gas. A feature that is found exclusively in sights with closed cases (see "Design"). Such cases are made airtigh...t, and the internal space in them is filled with an inert gas — for example, nitrogen — with a minimum content of water vapor. Thanks to this, the optical elements of the sight do not fog up from the inside, and metal parts do not oxidize due to contact with moisture. In addition, such an air-tight housing, by definition, is also dust and moisture resistant (see above).

— Rangefinder. A device that allows you to measure distances to objects visible in the scope. Do not confuse this function with rangefinder markings and other similar reticles (see “Reticle type”): in this case we are talking about a separate device, usually in the form of a laser rangefinder. Such equipment greatly simplifies measurements: there is no need to bother with special calculations for the angular dimensions of visible objects, just one click of a button is enough, and the accuracy of laser devices is very high — on the order of several centimeters at distances of hundreds of metres. The main disadvantage of this feature is the high cost; in addition, additional equipment increases the weight and dimensions of the sight. Therefore, built-in rangefinders are found exclusively in professional models designed for high-precision shooting.

— Level. A device that allows you to control the deviation of the sight (and, accordingly, the weapon) from the horizontal position — namely, the tilt to the right / left. Such a need arises primarily with high-precision shooting: even a slight slope, imperceptible to a person, can give a significant deviation, especially at a great distance. Levels may have a different design and principle of operation, but they are always set so that the shooter can see such an indicator at the same time as aiming. For example, in optics (see "Type"), a bubble bulb is placed above the lens or to the side of it, while in "night lights" and thermal imagers, data from an electronic sensor is projected directly into the eyepiece.

— Lantern. A flashlight mounted directly into the body or on the body of the sight. A rather specific function that is rare: at distances where optics are mainly used, a searchlight is needed, for "night lights" an IR illuminator is relevant (see below), collimators are more convenient to use with a separate underbarrel or hand "tactical" flashlight. However, the built-in lamp cannot be called completely useless. So, in optical sights, it is usually combined with a laser designator (see below), allowing you to effectively use the laser in low light conditions. And in the case of a collimator, the LEDs built into the frame are more compact than a separate underbarrel flashlight (which, moreover, can not be installed on every weapon that is compatible with a collimator).

— Laser designator(LTC). Device for quick aiming at short distances. The idea of such a device is extremely simple: a laser beam shows where the weapon is aimed, creating a clearly visible mark at the point of impact. This allows you to shoot accurately, even without looking into the main sight — including "from the hip" and from other emergency positions, which is especially useful in situations requiring maximum reaction speed. LCC is relevant only at minimum distances, but this is not a drawback, but a feature that can turn out to be a definite advantage. For example, a "laser" can be a great addition to a telescopic sight, which by itself is useless at short distances.

— Compatibility with night vision devices. Possibility of using the sight with separate night vision devices. Most often, this feature is found in collimator sights (see "Type") — it means that the brightness and colour of the collimator mark make it possible to clearly see it even through night vision devices. But optical models with such compatibility are extremely rare: firstly, it is technically difficult to implement, and secondly, for sniper shooting in the dark, there are specialized night and thermal imaging sights that are more convenient and effective than a combination of night vision devices with classic optics.

The type of mount supplied with the scope.

For normal mounting on a weapon, this mount must match the type of seat for the scope. The most popular types of mounts nowadays are on the Weaver / Picatinny rail and on the dovetail ; branded latches are noticeably less common, and some sights are supplied without mounts at all — this allows you to choose the option at your discretion. Here is a detailed description of specific options:

— On the Weaver / Picatinny rail. Fastening on a standard bar (“rail”) Weaver or Picatinny rail. It is considered the Western standard for installing a weapon body kit, but nowadays it is widely used around the world. It is worth noting that these types of slats, although similar in design, are not the same. They both have a T-shaped profile and transverse slots that allow you to securely fix the installed accessory in the chosen place, but differ in the size and location of these slots: they are wider in Picatinny rails and have a standard distance between centers. In fact, this leads to the fact that accessories for Weaver rails can easily fit on Picatinny rails, but not vice versa. In addition, Picatinny is considered more of a military standard, and civilian weapons are equipped mainly with Weaver rails. Thus, most of the complete rail mounts found among modern sights are desi...gned specifically for the Weaver rail, as it is more common and universal. However, exceptions are possible, so this nuance needs to be specified separately.

— "Dovetail". The seat of this type has a cross-sectional view of an inverted trapezoid, and the mount provides protrusions on both sides, which, when the sight is installed, “cover” this trapezoid. This type of mount is found mainly in air and sporting rifles, as well as in hunting weapons of a classic design. In the latter case, this choice is also due to aesthetic considerations — these mounts look neater than the gear "rails" of Weaver and Picatinny rails.

— Firm. Various specific fastenings not related to the standards described above. Often they are made not just for the products of a particular brand, but also for strictly defined models of weapons; one of the characteristic examples is the original seat on the high-end "sniper" Blaser R93. Branded devices can have a rather original design — for example, in some collimators for shotguns, a plate is used that is fixed between the butt and the receiver. In general, due to limitations in application, such fasteners are usually provided not as the only option, but as one of the options, in addition to the bar and/or dovetail.

Separately, it is worth touching on situations where several types of mounts are indicated in the characteristics of the sight at once. Most often this means that this model is available in different configurations, but there are other, more specific options — the presence of several types of mounts in the kit at once, an adapter from one type to another, or even a universal retainer that is also compatible with Weaver / Picatinny rails, and with a dovetail. Such details in each case should be clarified separately.

The country of origin of the brand under which the product is sold. Nowadays, the sights market is mainly represented by brands from such countries (in alphabetical order): Belarus, Great Britain, Germany, Spain, Lithuania, USA, Japan. However, there are other options as well.

There are many stereotypes about how the origin of a particular country affects the quality; however, nowadays, they have practically no basis. First, the origin of the brand is indicated either by the actual place of origin of the company, or by the country in which its headquarters is located; in both cases, this country does not always coincide with the country where the production is located and where the device was actually manufactured. For example, it is quite normal for the products of an American or German brand to be manufactured in Taiwan or Turkey. Secondly, the actual quality of a product is primarily affected by how it is positioned in the market and how carefully the manufacturer ensures quality control. As a result, paying attention to the "homeland" of the brand makes sense only when you fundamentally want or do not want to support a company from a certain country; in other cases, it is worth focus primarily on the reput...ation of a particular manufacturer.

The total length of the sight.

This parameter is important primarily for optical sights (see "Type"). Such devices can be quite large — from 20 – 30 cm in the most compact models up to 40 cm or more ; and the distance from the eyepiece to the eye when aiming must be strictly defined. So before buying, it's ok to clarify whether it will be possible to correctly place the selected model on the weapon. But collimators, even the largest ones, are very compact, usually there are no problems with their installation, so in such models the length does not play a special role.