A lot more goes into a proper bench press lift than a lot of people realize. One of the most common mistakes that I see is how far apart people place their hands on the bar. People will do a full bench workout and their triceps or shoulders will be more tired than their chest. The reason for this is most likely where they are putting their hands.
Ideal Grip: To get the best pure chest workout on a bench press, do a few practice reps just with the bar. A basic rule of thumb is that you want your hands to be placed so that when your triceps are parallel to the ground, you have a 90 degree angle at your elbow. Another way to get your ideal distance is to get into your body’s natural pushup position and measure the distance between your hands. Your body usually knows what works best and will automatically put itself in the most efficient position.
Feel free to lower beyond this 90 degree angle when lifting, it’s just a reference point for hand placement.
Variations: A lot of people either place their hands too close or too far apart. The close grip works your inner pecs and puts a huge load on your triceps and the wide grip emphasizes the shoulders. Most people lose some weight on their max bench if they have their hands too close/far.
I’m not saying the close and wide grips aren’t legitimate techniques. They’re actually very useful for building up the shoulder and tricep muscles necessary to improve your bench press, but they’re not helping you if you don’t know what you’re doing or why you’re doing it.
Just as one last tip, even if you are trying to work your shoulders/outer pecs, I wouldn’t go too too far past shoulde width on the grip and if you do be careful with the weight. If you’re not careful it can really wreck your shoulders.