Mr-155, rifle, smoothbore weapon

Mr-155 K – a new development of the Izhevsk mechanical plant. Reliable, high precision rifle, featuring affordable cost and unusual design in the style of “Military”.

The birth of semi-automatic rifles, MP-153 at the time caused a lot of noise. On the arms market of Russia, it was the only gun, allowing the use of any ammunition with a length of the liner 70 to 89 mm. Weapon has won many awards and has produced more than 10 years.

However, the arms market is not static. And the most advanced model can become even better. In the end, the Izhevsk mechanical plant in 2010 began to release a new model MP-155 K.

Review of shotgun MP-155 To

Mr-155 K and, or rather, the whole range of Mr-155 made under the trademark Baikal. The development began selling at the peak of Mr-153. It was important to rectify the shortcomings of the model, while retaining the simplicity of design and reliability.

The main drawback of self-loading rifles was its weight: at the time of the study demand foreign counterparts of such kind took the weight from 3.1 to 3.3 kg, while the MP-153 weigh at least 3.6 kg without ammunition. Furthermore, the lack of balancing and the lack of options such as the ability to adjust the butt and the lack of straps under the optical sight significantly reduced its competitiveness.

All these drawbacks have been corrected in the new line. As for the Mr-155 To what worked here not only designers, but also designers. The new model has a original design in the style of “Military”, designed specifically to attract a new generation of shooters, quite demanding to the design of the firearm.

The main design elements Mr-155 To similar mechanisms of Mr-155: engine gas, locking mechanism, adjustment of the pulse and so on. At the same time there are some differences: the trigger mechanism at its base, strap weaver and so on.

Advantages and disadvantages

Mr-155 K – smoothbore autoloading shotgun is designed for hunting and sport shooting. The phone is available with bolts of different lengths that provides an “omnivorous” guns: 76 and 70 for a 12 gauge.

• The main parameters of fire for the hunting rifle remains the accuracy and uniformity scree shot and sharpness. Target rifle with 35 m and then 50 m. Figures Mr-155 To fully comply with GOST, which requires:
  • the deviation of the STP from the center up not exceeding 150 mm;
  • the downward deviation is not more than 50 mm;
  • deviations to the right and to the left is 75 mm.

In fairness, not with all the ammunition the rifle can show a proper result. Hunters are recommended to experiment with several types of ammo to find the one that gives the greatest accuracy.

• Reloading the gun is performed automatically by the operation of the powder gases. The vapor-automatic adjustable, allowing you to achieve a sufficient level of reliability when using any fractions.
• Power is from detachable box-store. Capacity depends on caliber – 4-5 rounds.
• The receiver similarly, the model MP-155: the top part made of aluminum alloy, the bottom – fiber-reinforced plastic. The latter includes the butt and the pistol grip. As the experience of operating the Mr-155, this option is more than reliable.
• USM mounted on its own base, fully removable. Guns can be fired only single shots, which corresponds to the requirements of a hunting rifle. USM MP-155K is equipped with a non-automatic fuse. Feature of model MP-155 To is shutter delay: it holds the shutter in the rear position in the absence of cartridges in the store.
• The barrel is made from high quality gun steel. The receiver channel, the chamber and part of the gas engine – the gas chamber and piston, chrome plated. Thus, prevented the corrosion of metal.

Trunks originally designed for shooting lead and steel shot. Izhevsk plant (also known carbines MP-94 “Express”, Mr-43КН, MP-133, MP-233 MP-18МН, “North”, MP-161K, Mr-142К, Mr-143) offers interchangeable chokes of different value choke constriction that increases the range of the guns.

• The use of plastic in the design of the rifle is allowed to reduce its weight: without ammo all the model range, including Mr-155 To weigh in the range of 3.5 kg.
• The rifle comes with open sights and the rear sight has 2 possible positions: open and optical sight. In addition, Mr-155 is supplied To strap the weaver rail that allows mounting on a rifle optical sight, and even electronic guidance system. It is necessary to remove the detachable carrying handle rifle.
• The appearance of the product much more aggressive and brutal than a normal rifle Izmena. Anodized aluminum, black plastic complement and emphasize the design in the style of “Military”.
• Models are available not only for the right-handed and for left – handers with the handle and overcharge the window, throwing shells right and left, respectively.

The disadvantages of the rifle Mr-155 To the next.

• Weight, of course, still far from the ideals. Offhand shooting is pretty difficult, and after 5-6 hours of walking rifle seems to be too heavy.
• Unregulated butt creates significant discomfort.
• There is no possibility to switch between removable and rifle shop.
• Design is designed for its user group. Experienced hunters usually prefer a more elegant and lightweight model.

Photo of shotgun MP-155 To

Purpose

• Mr-155 To initially was seen as a hunting rifle. High accuracy and ability to shoot steel shot makes the rifle very best value for hunting medium animal and large bird.
• Expanding the ability to set an optical sight. However, for varminting it is, nevertheless, not good.
• Aggressive styling makes the gun shows promise as a means of self-defense: defeat a major fraction from a distance of 20-35 m will stop any attacker. High accuracy provides hit at least 80% of the fraction.
• This figure allows you to use the rifle for sport and recreational shooting, in which a large weight is an advantage, as it reduces the impact.

About the special version of MP-155 will be discussed below.

Varieties

• Mr-155 To produced for the 12 gauge, but with different length of the chamber 70 and 76 mm. This allows you to use cartridges with casing of different lengths.
• The model comes with different length barrels – 510 and 610 mm.

Specifications

Custom quality rifles MP-155K is similar to the characteristics of the entire line Mr-155. Muzzle constriction for Mr-155 To offers for lead and steel shot, ear appropriately marked.

Gun weight is listed without bullets.

Design

Rifle Mr-155 It consists of several main modules.

• The barrel with the gas chamber – the trunk is executed from stainless steel, the channel and chamber chrome plated. Lockable trunk swinging larvae: it is located in the stopper and engages with the shank of the trunk. The magazine tube is hollow, it is the return spring. Annular gas piston located around the magazine tube under the barrel. The vapor-automatic can be adjusted, but it is necessary to make a partial dismantling. On the barrel and receiver has charge.

Shutter – longitudinal sliding, locking occurs due to the lugs of the wedge, which is included in the groove in the clutch barrel. Rising wedge in a rear position with the bolt.

• Box perehvatyvaet and under-barrel store consists of two parts: the upper is made of anodized aluminum and the bottom of impact-resistant plastic. Shop for 5 rounds, box type. The unlocking lever is flat, on the top handle. The store can be installed limiter.
• The mobile system is a shutter frame, shutter with a wedge, arm overcharge and the piston regulating the speed of the rollback of moving parts. The speed controller is installed on the piston and includes a valve ring, a spring and adjusting nut. This device allows the use of ammunition with different ballistic characteristics. In addition, using the controller can compensate for the effect of temperature and humidity, relieving the excess pressure of powder gases into the air.

Shutter delay allows you to stop all moving parts of the rifle in the rear position at the moment when all the bullets are spent.

• The recoil spring is in the magazine tube, provides automatic reloading of the rifle.
• Trigger mechanism – is placed on its base, hammer type. USM is located inside the housing of the box and is removable module. The mechanism is equipped with non-automatic push-button guard that blocks the trigger. It is located on the rear area of the trigger guard.

On a gun with open sight: the rear sight is adjustable horizontally, fly vertically. Has 2 positions for open sight and diopter. The rear sight is mounted in a removable carry handle rifles. In addition, there is strap weaver: after removing the handle can be mounted on a rifle optic or reflex sight.

• Buttstock with pistol grip is made from high impact reinforced plastic.
• The forearm is of type ventilated, made of plastic.

The gun is compatible with all manufactured chokes.

Picking and packing

Standard products includes:

• cardboard box;
• 3 choke tube;
• the universal key;
• passport MP-155K.

Muzzle replacement liners sold separately. The design of the Mr-155 allows you To replace the barrel additional without any prior manipulation.

The principle of operation

Mr-155 It relates to self-loading rifles. This mechanism is based on the use of pressure, which is created by the powder gases. The bore is connected with the gas chamber of the venting channels. Porohovye gas passing through them, exerts enough pressure on the mechanism of recharge. The existing speed controller allows you to increase or decrease the gas pressure.

Use regulator is recommended only after shooting about 50-100 rounds. The adjusting nut located on the piston, turn counter-clockwise 1-2 revolutions when the pressed retainer. Use the universal key. When shooting heavy bullets turn the screw clockwise.

The mechanism of action can be described by the following scheme:

• when you press the trigger the hammer hits the firing pin and acts on the retinaculum. Latest releases perehvatyvaet, and round from the magazine is fed to the tray;
• under the influence of the powder gases, the piston with the bolt carrier moves backwards, the bolt carrier acts on the wedge and produces the unlocking of the barrel;
• the movable system as a whole moves backwards: while the used cartridge case is extracted from the chamber and removed from the box. The hammer cocked;
• the return spring causes the movable system to move forward: the tray, the cartridge is raised and the cartridge is in the chamber;
• when the breech returns to its forward position, the barrel is locked by movement of the bolt with the forward piston is raised and the wedge enters the recess of the coupling. You can perform the following shot;
• after all the cartridges are expended, the bolt stops at the rear position due to back delay.

Mr-155 K is designed for firing ammunition with lead and steel shot. However, the muzzle of the narrowing is not as versatile: inserts, intended for shooting with lead shot, there is a marking Lead, steel shot is “Steel”. Cartridges can be charged independently, but it is necessary to adhere to the manufacturer’s recommendations and not to change the linkage of gunpowder and weight fraction.

Preference is given to ammunition with plastic cartridge, cartridges with a metal sleeve is not recommended.

Use bullets with a diameter of 0.2–0.3 mm less than the diameter of the barrel or muzzle of the contractions. Caliber bullets from solid materials – steel, brass, do not use.

Disassembly

For care of rifle – cleaning and lubricating, enough partial disassembly of the mechanism. It is necessary to pay attention to individual parts. So, when you detach the wedge from the shutter of the side groove of the wedge releases the ball. The item is small and easy to lose.

Disassembly of the regulator to conduct highly undesirable: the preload of the valve spring is produced with great effort, and to reproduce that effort at home is almost impossible.

Partial disassembly includes the following steps:

• Unscrew the fore-end cap and remove it;
• with the grip shift back 10-20 mm shutter and take the gun out of the box;
• remove the handle overcharge, applying force perpendicular to the axis of the shutter;
• consistently remove the piston, bolt carrier, bolt with a wedge, then the return spring and a ring buffer;
• out of the box, knock out the 2 pins that hold the trigger Assembly and removed last.

In this state the rifle is available for cleaning and lubrication.

• If repairs are required, permitted, as a full disassembly of the rifle, which includes the described manipulation, the detachment of the buttstock and disassembly of the USM.
• Further disassembly is permitted only in the weapons shop. Assembling the rifle in the reverse order.
• For lubrication use gun oil, cleaning brush, cleaning rod and clean wiping material. To remove strong svintsovy allowed the use of brass mesh or brush.

Stored Mr-155 in a disassembled, unloaded. Ammunition should be stored separately.

Tuning

The design of the Mr-155 It provides some possibilities for tuning. The choice of fixtures depends on the purpose of the rifle.

• Replacement open sight collimator or optical tuning even difficult to call. And, by the way, the weight of the gun in this case becomes plus so no restriction on the weight of the sight.
• Be installed and other fixtures: gas muzzle compensator, for example, or an underbarrel flashlight.
• One popular solution is the lengthening of the store. For hunting, perhaps this is an improvement to anything. But for shooting sports the increased MAG size to 10 rounds more.

Price and owner reviews on a semi-automatic shotgun Baikal MP-155 K (Mr-155K) is given below.

Price

The cost of Mr-155 in the Moscow shops reaches 30800 R. the gun used can be found for 20,000 R.

The cost of ammunition is determined by its ballistic characteristics.

Reviews

Almost all the owners of Mr-155 To note the high accuracy of the battle, and regardless of how you are shooting buckshot or bullets. A big plus is that the barrel does not overheat even during active shooting: the excess of the powder gases are guided through recesses in the forend.

• Handguard is comfortable in coverage. However, his material – plastic, is a little uncomfortable: slips out of the steamy palms.
• What is the clear disadvantage is the sharp rim of the receiver above the trigger: quickly rubbed on her finger.