Let's explore stats.

What exactly is *insert weapon stat here*?

Given the fact that many people are wondering what does some particular stat mean, and what does it affect, let's take a moment to explore the details behind the in-game stats by taking a look at the table below, and then see the what each individual stat means. We can subdivide the stats by two types:
1) Weapon stats - stats that affect the weapon's behaviour
2) Weapon modifiers - stats the affect the weapon's behaviour in different player stance.

Weapon Stats

Abbreviation Stat Short Description
DMG Damage The base damage the weapon inflicts when hitting a player without armor.
SPR Spread The bullet's initial angle (wider / tighter).
REC Recoil The backwards movement of the gun.
HREC Horizontal Recoil The left-right kick of the weapon when it recoils on shot.
VREC Vertical Recoil The up-down kick of the weapon when it recoils on shot.
DVA Deviation In game mechanic used to simulate realistic spread. (See more below)
SPD Speed The initial speed at which the bullet exits the muzzle.
PWR Body Hit Impact Power A number indicating the power of the weapon as a combination between the bullet velocity and it's damage.
ZRNG Zero Range The range at which the bullet does not have any vertical drop towards the ground.
RNG Range The maximum zeroing range before the bullet velocity drops and the hit damage goes to 0.
TBS Time Between Shots Self explanatory, measured in seconds.

Weapon Accuracy Modifiers

Abbreviation Modifier Short Description
AIS Aim Down Sights The spread modifier (usually reducing) coefficient when looking through a sight or scope.
AIM Aiming The spread modifier (usually reducing) coefficient when aiming.
RUN Running The spread modifier (usually increasing) coefficient when running.
WLK Walking The spread modifier (usually increasing) coefficient when walking.
CRCH Crouching The spread modifier (usually reducing) coefficient when crouching.
Details on the weapon stats

Damage

Damage is pretty self-explanatory. It's the base damage that the weapon inflicts on hit. But that indicates only the body damage without armor. We can take a look at the different damage values on a weapon based on where it hits, and how well protected the player is.
For example the Scarl weapon's base damage is 41, and here are the damages against different armors:

102.5

71.75

61.5

46.13

41

28.7

24.6

18.45

Spread

Spread is best understood by looking at what holes the shotgun bullets leave against a wall. The spread changes with distance as the bullets travel in a cone like area, and depending on the weapon, the "cone" varies in size. The shotgun is the best example, since it fires more than 1 bullet at a time, but that doesn't mean the single fire weapons do not posses such stat. They do, and it is represented by the random angle the bullet starts from initially. If we fire more than once against a wall we can clearly see that it does the same as the shotgun, but most probably at a smaller radius. In-game the spread is also affected by the player's movements, e.g jumping, running, walking, crouching etc.

Recoil

This is the base stat for recoil. It's split into two parts: horizontal and vertical recoil. Each one of them is coefficient of the horizontal and the vertical angle deviation which will kick the weapon with, when firing. This is most notable when we shoot with a Sniper Rifle and right after the fire we see how the scope goes into a upwards motion in a random manner. Equipping the weapon with a compensator gives greater stability and thus less deviation and better recoil handling.

Deviation

One of the most asked questions: what is deviation?
This stat is a little bit more specific, as it is a mechanism implemented for PUBG to induce a realism into the recoil. It only applies when shooting in third-person or first person while aiming with right-mouse or without aim, and it adds up a little bit of randomness to the overall angle at which the bullet will initially aim towards. When we use Aim Down Sights the weapon uses only it's own specific inaccuracy properties and the deviation is not applied.

Speed

Measured in meters per second, that is the initial speed of the bullet right after firing. It's one of the key properties for determining the power, damage and range of the weapon. The force of gravity starts acting upon it immediately, meaning the greater the velocity is - the further the bullet will travel, and also the more accurate it will be in shorter distances, but still the gravitational downwards pull is negligible inside the range of the zeroing distance.

Body Hit Impact Power

Although there is no official information regarding the weapon's power, it seems that it is combination of the weapons speed and it's base damage. Example given, the AWM Sniper has one of the highest base damages 132 and one of the highest speed 910 m/s - in combination they give the highest possible power for a weapon in PUBG - 40000.

Zeroing Distance

The zeroing distance indicates the maximum accurate distance the weapon has. Equipping an 8X Scope we can see that pressing PAGE UP and PAGE DOWN we can change the zeroing distance between 100m and 1000m. Simply explained, when an object is 100m away and the zeroing distance is set to 100, it means the bullet will hit right exactly at the center of the scope. This goes for any allowed distance by the scope. By default all weapons are set to 100m and have a maximum amount of zeroing distance, which indicates the aiming capabilities of the weapon.

Range

Range is also a self-explanatory stat, since it indicates the maximum travel distance of the bullet. If the range is 1000m, it means that the bullet cannot travel further than that, no matter the starting angle. At 1000 meters it's speed will drop to the point where it does not do any damage to the player. The most common factor that affects the range is the bullet's initial speed.