Anyone who is interested in firearms or just a curious reader of magazines and books on weapons-related topics is constantly confronted with the terms “Picatinny bar” and “Vivera”. Both one and the other are auxiliary devices for equipping with additional equipment, without which modern small arms are inconceivable. This article is intended to give a popular definition of what the Picatinny rail is and what is its difference from the Weaver rails, as well as to describe the features of both and their designations according to NATO classification.
Picatinny rail
The name comes from the English Picatinny rail. Structurally, the device is a rail-bracket, reminiscent of the letter "T" in cross section. It is used on various small arms as a universal mount for optical, collimator sights and other auxiliary devices, including support bipods, tactical pens, laser target indicators, lighting devices and other equipment.
The common standard was developed by the US military research and production organization Picatinny Arsenal. This standard is known in America under the designation MIL-STD-1913. For NATO, it has another designation, namely: STANAG-2324. Picatinny rail allows not only to rigidly fix the additional device on the weapon, but also to move it back and forth, fine-tuning for each individual shooter. Directly attaching to the bar is carried out using bolts and levers, which allows you to quickly change the configuration of equipment, adapting weapons for a specific task. To exclude deformation under the influence of temperature differences that occur during heating and cooling of the barrel, the Picatinny rail has transverse slots done with a constant pitch. Their sizes and pitch are set by the general standard (slot - 5.23 mm, pitch - 10.01 mm, depth - 3 mm). In addition to the cooling function, the slots play the role of position locks for many auxiliary devices.
Rail weaver
The Picatinny rail differs from the Weaver only in the size of the slots. In fact, the Weaver rail is the same design, but does not meet the MIL-STD-1913 standard. As a result, most accessories that are mounted on Picatinny rails can also be mounted on the Weaver rail. The width of the Vivera slots is 0.180 ", but, unlike the Picatinny rails, the Vivera slots do not necessarily have the same pitch from each other, so not all auxiliary devices designed for mounting on the rail will fit the Picatinny rail.
Advice to airsoft players
In conclusion, we draw the attention of airsoft players to the fact that in the case of all kinds of copies of small arms manufactured by the People’s Republic of China, the standards specified in the article are not maintained, and often the width of the slats and slots in them are arbitrary sizes. And this applies not only to Picatinny rails, but also to device mounts. Therefore, buying such a replica, you should immediately select the device that is paired with it, otherwise it can be very difficult to find a suitable part later.