Rarity Levels
Common or White is the easiest found rarity. The basic form of several weapons (Pistol, Revolver, Assault Rifle, Tactical Shotgun) is found as greys very commonly.
Uncommon or Green is the second most common. A basic form with usually 1 to 3 more damage is found. However several weapons are green onwards (EG: Pump Shotgun, Hunting Rifle, Tactical SMG) can be found.
Rare or Blue is the middle tier rarity. Basic forms, not advanced weapons, can be found - every single weapon apart from a Guided Missile, a Semi-Auto Sniper Rifle and a Heavy Shotgun or an advanced gun can be found in blue. Blue weapons have about 5 more damage.
Epic or Purple is the second best rarity. No Basic forms can be found in Purple - they are upgraded. Semi-Autos and Heavy Shotguns can be found purple onwards.
Legendary or Gold is the best tier. They are found primarily in Supply Drops - balloons that spawn in shrinking intervals of time, starting at 3:00 min. They do the most damage - usually 6 to 10 more than the grey ones. There are only two Legendary consumables - bush and chug jug.
Basic and Advanced Forms
The revolver can be found in 4 different rarities. White, Green, Blue, and Purple.
The Hand Cannon, a different weapon, is very similar with a clip of 7 rather than 6. It does more damage and fires slightly faster and accurately with a 9 damage difference.
Best Answer
In my experience, the rule seems to be that you and the person you kill must be within 20-30m of the location. I know that I was standing on the bridge by tomato town and sniped someone in the restaurant, and it didn't count as a kill, but when I was around 20m outside tomato and I killed someone who was directly next to me, I did get the kill