Aiming
Aiming
First, make sure you have the mousedelayfix mod installed. If you are using Forge, the Patcher mod includes this. Lunar Client has this built in.
The reach distance in Minecraft is 3 blocks, starting from the center of your head. This means that in order to get the most amount of reach, you should aim parallel to the ground in most cases.
In the image, although both players are 3 blocks away from each other, the player on the left cannot reach the other player because he is looking down.
In the image, although both players are 3 blocks away from each other, the player on the left cannot reach the other player because he is looking down.