PlayerUnknown's Battlegrounds is a breeding pool for misinformation, and in some ways that's wonderful. Every time I get into a game with a new person I am given a new piece of information. The utility belt has carrying capacity. The SCAR with attachments has better control than the M16. This one building, yes this one, has a better loot table than all of the buildings around it.
PUBG is the Pokemon of the contemporary period, proliferating rumors, half-facts, and complete lies in a grand play of almost-confirmed information by players, forum posters, and YouTube videos. It's a rare experience when everything can be data mined, but that doesn't prevent it from happening.
I was pleased to recently come across a video from YouTuber jackfrags where he does some "mythbusting" around the guns, armor, and other equipment in PUBG. Interesting enough, this video is from May and has more than half a million views, but (perhaps unsurprisingly in a game with millions of players at this point) I still don't think that the information that he provides there has fully entered into the player community.
The video provides important information about the basic use of certain weapon attachments. For example, I've heard conflicting accounts of what suppressors do in the game. Are these silencers like other games where the decreased sound brings decreased damage? According to the testing in the video, no. Silenced rifles do the same amount of damage.
Other important tidbits become general rules: The level of armor that you have equates roughly to the number of additional hits you can take from guns. The same goes for helmets. Bullets don't travel through doors until you knock a chunk of the door out, and car doors are completely bullet proof. It takes three Molotovs or frag grenades to destroy any vehicle, and two will destroy a bike.
Watch the entire video for the breakdown. It's an incredibly helpful thing, even though there have been some patches and updates since its release, because it gives you a baseline for understanding how weapons perform. Also, a frying pan can destroy a car.