Comparison Crosman TR77 NP vs Crosman Nitro Venom

The type describes the basic principle of operation of the rifle. Nowadays, you can find pneumatics with a spring-piston principle of operation (with a conventional or gas spring), with pre-pumping (PCP), with pumping before each shot ( multi -compression rifles), powered by carbon dioxide cartridges and with an electric drive. Here is a more detailed description of each of these types:

— Spring-piston. As the name suggests, the basis of the mechanism in such rifles is a spring-loaded piston moving in a cylinder. The weapon is cocked manually (usually by a lever or a broken barrel), while the piston is retracted and fixed, the cylinder is filled with air, and when the trigger is pressed, the piston is released and moves forward under the action of a spring, pushing air from the cylinder into the barrel. Rifles of this type have simplicity and reliability of design, low cost, unpretentious maintenance, as well as ease of repair and tuning; they are considered an perfect option for beginner shooters, as well as for lovers of entertaining "shooting" at short distances, there are also models for airsoft among them. It is also worth mentioning the excellent repeatability of shots (with each cocking, a strictly defined portion of air enters the cylinder) and insensitivi...ty to heat and cold. On the other hand, such rifles require cocking (and most often reloading) before each shot, which can be quite tedious; and the operation of the piston mechanism creates a specific recoil, which adversely affects accuracy and makes it difficult to select optical sights (requires special optics, originally designed for this application). In addition, pneumatics of this type cannot be kept charged for a long time — with prolonged compression, the mainspring loses its properties.

— With gas spring. According to the general principle of operation, rifles of this type are similar to the spring-piston ones described above. The difference lies in the fact that instead of a conventional metal spring, they use a sealed reservoir with a special gas, which plays the role of a spring — shrinking when cocked and expanding when fired. This design has a number of advantages over conventional spring-piston. Firstly, the whole mechanism is much smoother and quieter, and the recoil is softer, which improves accuracy and simplifies the selection of optics. Secondly, the gas spring does not change its properties as it wears out, and such weapons can be stored even in the cocked state. Third, repairs and maintenance for gas springs are less frequent and less expensive (in terms of the number of shots between workshop visits). The disadvantages of rifles of this type, in addition to the need to cock the spring before each shot, include a slightly higher cost than that of classic spring-piston rifles, as well as sensitivity to cold: when the temperature drops, the gas pressure in the spring decreases, which worsens efficiency.

— PCP (pre-pumping). The energy source in rifles of this type is a built-in reservoir containing air (or other gas) under very high pressure — about 200 or even 300 atmospheres. Such a reserve is enough for at least several dozen shots, and a compressor, a scuba cylinder or a special high-pressure pump can be used to fill the tank (sometimes such pumps are even supplied as a kit). In general, PCPs are considered the most advanced type of pneumatics, and these are the rifles used by professional hunters and sportsmen. This is primarily due to the fact that such a design allows you to achieve a very high speed of the bullet, and the recoil is almost imperceptible — all this allows you to accurately shoot even at long distances. On a fresh gas station, the rifle gives excellent repeatability of shots; however, as the gas is consumed, the initial velocity of the bullet decreases, however, in advanced models, a gearbox may be provided to compensate for this phenomenon (for more details, see “Air supply by the gearbox”). PCP pneumatics can be easily multi-shot and provide very simple and convenient ways to feed the next bullet into the barrel. The main disadvantage of such rifles is the high price.

— Multi-compression. Another variety of rifles with a built-in reservoir; however, unlike the PCPs described above, the reservoir must be inflated before each shot. To do this, the design provides for a built-in pump controlled by a lever or other similar device; to pump enough air, usually, you need to make several movements. In such rifles, there is practically no recoil, while they are noticeably simpler and cheaper than PCP pneumatics, but they are inferior to it in terms of power. In addition, pumping up the tank before each shot is quite a tedious task; and the volume of air supplied to the tank at each filling (and, accordingly, the working pressure in the tank) will depend on the number and amplitude of movements made by the pump lever. On the one hand, this allows you to adjust the power directly “on the go”: for example, for a short range where maximum bullet speed is not required, you can not fully pump up the rifle in order to save energy. On the other hand, the actual volume of air and the pressure in the tank will be somewhat different with each recharge, even with the same number of lever movements. This negatively affects the repeatability of shots. Due to this combination of features, multi-compression models are not very popular nowadays, and their purpose is mainly recreational shooting.

— Gas balloon. A type of pneumatics powered by interchangeable cartridges of gas, usually liquefied carbon dioxide. As in PCP, such a tank allows you to make a lot of shots — even a traditional 12-gram can is usually enough for several dozen; and some models use 88g carbon dioxide containers. At the same time, the rifles themselves are cheaper than PCP, but they have less power. It is also worth noting the rather specific characteristics of carbon dioxide as an energy source. On the one hand, it maintains working pressure for quite a long time — it does not decrease as long as carbon dioxide remains in liquid form in the cylinder. On the other hand, the actual gas pressure depends on the ambient temperature, and the initial velocity of a bullet for such pneumatics can change markedly even with daily temperature fluctuations. And of the unambiguous shortcomings of such rifles, it is worth noting that for them you have to buy not only bullets, but also gas.

— AEG (electrically driven). Pneumatics that uses an electric motor drive as a power source. According to the design of the working mechanism, it is similar to the spring-piston mechanism — the basis of this mechanism is a cylinder and a spring-loaded piston. However, the piston in this case is not retracted manually, but with the help of the mentioned electric motor. For the shooter, this means, first of all, that the rifle does not need to be cocked due to muscular strength — for a shot, it is enough to press the trigger, the rest will be done by the electric motor. In addition, in such pneumatics, automatic firing mode can be provided without problems (see below). Note that for a number of reasons this principle of operation is practically not found in traditional pneumatics, but it is very popular in airsoft models; such rifles (“drives”) often copy real military weapons.

The muzzle energy provided by the rifle.

Muzzle energy is the kinetic energy of the bullet at the exit from the barrel. This energy, in turn, depends on two factors: the mass and the muzzle velocity of the bullet. Thus, this indicator directly describes the overall power of the rifle: higher muzzle energy allows you to effectively fire at longer distances and/or heavier ammunition. On the other hand, an increase in power accordingly affects the cost of weapons.

Note that muzzle energy can be grounds for legal restrictions on the purchase/use of pneumatics. So, in some countries in the post-Soviet space, the maximum value allowed for freely sold rifles is 7.5 J — a special permit will be required to purchase more powerful weapons. And most freely sold rifles in such regions have a power of the order of 3 – 5 J. Such legal restrictions should be clarified separately. Lower rates are found mainly among “soft” pneumatics for airsoft (airsoft), using 6 mm plastic balls. For such models, a value of more than 2 J is already considered very solid, and in games such rifles are used with a minimum distance limit — for example, 15 m or 20 m (so that a shot from too close a distance does not injure the player).

It is also worth saying that the claimed characteristics of air rifles may, at first glance, not correspond to physical calculations. For example, for a model for the same 7.5 J..., the initial speed of 250 m/s can be claimed in the characteristics; for a 4.5 mm bullet weighing 0.5 g (the average, most popular weight), this would correspond to an energy of as much as 15.6 J. However, there are no inconsistencies here: such characteristics mean that the muzzle velocity was measured for a lighter bullet (for example, 0 .2 g), which accelerates more strongly at the outlet of the barrel. Accordingly, with heavier ammunition, the speed will be lower; it can be determined using special formulas or online calculators.

The type of mount for mounting sights provided in the design of the rifle. Most often in such cases we are talking about an optical or collimator sight; and the most popular mounting options are Weaver/Picatinny rail and dovetail. Here are their features:

— "Dovetail". This type of mount has a cross-sectional view of an inverted trapezoid (expanding upwards); the clamp on the sight covers this trapezoid from two sides, and the transverse cutouts, unlike the Weaver / Picatinny rails, are not provided for in the design — fixing in place is carried out in other ways. Dovetail mounts were originally used in civilian hunting rifles, as well as in Soviet-style military weapons. Nowadays, due to their simplicity, low cost and versatility, they are extremely common in air rifles. In addition, we note that you can even install a Weaver / Picatinny rail on a dovetail (such rails are available separately) and use a sight with the appropriate type of mount.

— Weaver / Picatinny rail. Fastening in the form of a bar with a T-shaped profile and characteristic transverse slots — they serve to rigidly fix the installed accessories in one place. Technically, Weaver and Picatinny rails are different types of mounts, they differ in the size of the slots; these differences are such that the sights and other “body kit” for the Weaver rails easily get on the Picatinny rail, but the opposite option is far fro...m always possible. However, in the civilian market, most weapon accessories for such slats are made specifically for the weaver, so this nuance, most often, is not fundamental, and both types of slats are combined into one category.
In general, for a number of reasons, such straps are much less common in air rifles than the dovetail. At the same time, classic pneumatics are most often equipped with Weaver mounts, but in airsoft copies of real weapons, Picatinny rails (or compatible NATO STANAG 4694 rails, also known as RIS 22 mm) can also be used.

— Is absent. The absence of any standard mounts for the sight in the design of the rifle. Most often, this designation means that the rifle is equipped with a classic front sight with a whole and does not require the installation of additional sights. However, there is also a more specific option — pneumatics, in which original mounts are used to install optics or a collimator, which are not related to the standards described above. Such rifles can be supplied with or without scopes; there are even models with non-removable optics, although extremely rare.

The degree of magnification provided by the rifle's complete optical sight; for models with variable magnification, the entire adjustment range is indicated, for example 3 – 9x.

For sights of this type in general, see "Aiming Device". And several points depend on the degree of increase at once. On the one hand, a higher magnification allows you to better see small and/or distant targets and facilitates high-precision shooting; on the other hand, it limits the angle of view and significantly affects the cost of the sight, and sometimes also its dimensions and weight. And since air rifles are mostly not designed for long distances, the magnification of complete optics in them usually does not exceed 9x, and one of the most popular options is 4x. However, there are exceptions: in powerful high-end pneumatics, you can find sights with a maximum magnification of 24x and even higher.

Actually, the manufacturer most often selects the magnification of optics for the ballistic characteristics of the rifle. So, when choosing this parameter, it often turns out to be secondary, and it makes sense to focus primarily on the muzzle velocity of the bullet and the firing range for which the weapon is designed — usually, the capabilities of complete optics are quite enough for this. It is also worth mentioning the variable magnification sights mentioned at the beginning, which are quite common nowadays — they are somewhat more complicated and more expensive than fix...ed optics, but they allow you to adjust the magnification to the specifics of the situation.

The working length of the rifle barrel is from the chamber where the bullet is loaded to the muzzle. The shortest barrels found nowadays have a length of just over 200 mm(and in some AEGs even less than this value); the longest reach 500 – 600 mm.

There is a stereotype that the muzzle velocity directly depends on the length of the barrel. In firearms, this is true — but not in pneumatics. Firstly, in such rifles, the initial velocity depends on a number of other indicators — pressure, the quality of the barrel treatment, the efficiency of the valves, etc. on the first 20 – 25 cm of the barrel, then the gas pressure drops noticeably. The exception is PCP rifles, in which the longer barrel really makes it easier to achieve high speeds. However, again, so many additional factors affect the final result that models with the same barrel length can differ markedly in initial speed.

The second common stereotype is that a longer barrel improves accuracy and accuracy. This is true in the context that a longer barrel allows for a greater distance between the front and rear sights, making it easier to aim carefully. Technical accuracy does not depend on the length, but on the quality of the barrel processing.

Summing up all of the above, we can say that the length of the barrel for an air rifle is more of a reference than a really significant paramete...r, and when choosing, it is better to focus on more "close to life" characteristics — first of all, directly claimed muzzle velocity.

— Tree. A classic material used in firearms and then pneumatic weapons since ancient times (in fact, since its inception). Wooden stocks are strong enough on their own, and in modern rifles they are also amenable to special treatment to protect against dampness, temperature changes, etc .; while the rifles have a nice appearance in a classic style. At the same time, the wood is prone to abrasion, scratches easily appear on it, and there is a possibility of cracks. When used in simple conditions, such as periodic "shooting" in the country, this does not matter, however, for example, a wooden stock is not suitable for hunting — at least because it will quickly lose its "presentation". At the same time, this material is also somewhat more expensive and more difficult to process than plastic that is more resistant to “troubles”. Therefore, today the tree is used mainly in pneumatics of the middle and upper price range and is designed for those who are primarily interested in the aesthetics of weapons.

— Plastic. One of the most popular materials for the manufacture of modern pneumatics. Such stocks are easy to manufacture and inexpensive, while the plastic can be given a rather complex shape without any problems, which, in particular, facilitates the installation of various adjustment systems (see “Cheek Adjustment”, “Butt / Stock Adjustment”). However, its main advantage is practicality: this materia...l is resistant to impacts, cracks and scratches, comparable in strength to wood (or even superior) and has a small weight. As a result, plastic has become widespread in almost all price ranges.

— Aluminium. A fairly advanced material that combines low weight and high strength. On the other hand, aluminium stocks for classic pneumatics are generally expensive, and therefore are used mainly in high-end professional models (although there are exceptions). But in airsoft rifles that copy real weapons, the situation is somewhat different: there aluminium can be used as a simpler and more affordable alternative to steel (from which gunshot prototypes are made).