The Tick-rate of your server is the number of times your server ticks or refreshes in a second. While playing CS: GO you will hit the enemy with all the ammo that you have but the server will register it as a miss. This is only because of the slow tick rate. At standards, this rate should be 64 ticks per second, but most of the players prefer to play on a server with 128 ticks per second.
This guide will show you How to Change Tick-rate in CS: GO.
How To Change Tick-Rate In CS: GO
First that you need to do is open your Steam Library and find CS: GO.
Right-click on the game and then select properties.
Once you open the new window, you will come to General menu, and go all the way down to Launch Options.
In Launch Options copy the following link: -novid -tickrate 128 +mat_queue_mode 2 +cl_forcepreload 1 -novid -nojoy
Then press Ok to confirm the changes.
Once you copy the link in the Launch Options, your game server will be set to 128 ticks per second.
Now just open your CS: GO and test it with your friends.