As any lifter who has chased a PR knows, the bench press can leave your shoulders achy. The problem is often front-sided shoulder pain.
Many lifters have no idea where their optimal hand width should be on the barbell. Using the grip that allows you to press maximal loads can actually lead to pain and injury. The fix? Narrow your grip.
Your ideal hand placement is going to depend on your body and current physical presentation, not your willingness to move max weight with ugly form.
A wider grip increases front-sided shoulder stress due to larger moment arms, but also accentuates the amount of emphasis placed on the pecs and anterior deltoid, which are usually overworked to start with. Using a narrower grip places the shoulders in a more neutral and centrated position. It also distributes more muscular force into the triceps, which directly reduces the force requirements of the pecs and delts to complete a lift.
Err on the side of caution and go narrow. Start emphasizing a narrow-grip bench press in blocks of your training. Using a thumbless “false grip” on the bar can also get the shoulder in a neutral position by reducing the carrying angle between the upper arm and the torso.