Typically, when a gun sprays bullets for an extensive amount of time, it would start to heat up.
So, to add as a limit to sprayers and encourage short bursts, spraying after a certain amount of bullets (each gun has it’s own amount), the gun will start to emit smoke and become less accurate the more the gun is shot before cooling. Guns will lose durability. But in 4.0 or 3.0 or both, I would like that the guns last a good amount. Cuz shooting a couple bullets and you get -1% is a bit too much. But if this gets added, spraying and iverheating will cause the gun to lose durability quite quick.
Ideally, I think guns in Unturned should degrade relatively slowly unless overheated. Should go hand-in-hand with my previously suggested gun jamming mechanic to replace the bland stat dropoff durability currently imposes.