After the first shot, the Desert Eagle's spread increases, making follow-up shots less accurate. Instead of spamming Deagle shots, it's often more effective to C-Tap and switch to Sawn.
While firing uzzi from further, using w + e/q will make you harder to track by the opponent then just using w or e or q while is not making it for you really much harder to track the opponent.
Flick: You can estimate where the player is and shoot without the aim actually being displayed. Just guess where your opponent is and press fast right+left click. Some people told me they actually do the opposite and it works good, like left click and just after that rightclick.
If the distance is good enough, starting without aiming on uzzis will do insane damage since shooting uzzis without aiming will have nospread. Same goes for AK but for AK the distance need to be bigger.
Also, uzzi fires when no aim not in the spot where your normal aim would be, you need to test the waters a little in order to do this.
In the first clip you can see the damage difference of me not aiming and my opponent aiming.
if you shoot sawn and then sawp to uzzi and shoot 20 bullets or more, it will cancel sawns reload when you swap back to it. This also works on deagle if you do 1 ctap i think.