4 seam FB, vs 2 seam FB

At what age should this usually be developed. Is hand size important to this? They both have the same rotation, just the 4 seam rotates less for less movement?

I don’t want to instruct you wrongly, so take all I say with a grain of salt and wait until someone else with more knowledge agrees.

  1. Any age (in my opinion. It’s just another fastball.)
  2. Hand size is not important, it’s a fastball. Although I read somewhere that if you’re really young, you can grip your normally 2 finger pitches with 3 fingers.
  3. No! The 4 seam typically has the most velocity of all a pitcher’s pitches. Therefore, it rotates the most.

I’m assuming your main question is when should someone start throwing the 2 seam? If not I made myself look dumb. :oops:

anyone else?
BTW i was told 4sFB has less rotation so it dont break as much.

Agreed, 4 and 2 seam fastball should be able to be taught whenever the pitchers hand is big enough not to have to throw only a palm ball. There isn’t break to a 2 seamer, but run. Right hand movement should be into a right hand hitter. 4 seam has a straighter action both because of rotation and how the seams are disrupting the air flow.

I agree with bu

[quote=“Plaz”]anyone else?
BTW i was told 4sFB has less rotation so it dont break as much.[/quote]

An excerpt from Tom House’s The Pitching Edge:

Throwing across four seams is a power pitcher’s fastball grip. Biomechanically, it maximizes force through the center axis of the ball and imparts a reverse spin on the ball that works in the airflow to minimize the pull of gravity, The ball appears to hop. Actually, it drops less than other types of fastballs.

[Throwing with two seams] [is] for location pitchers who want to run or sink… the ball. The middle finger will impart rotation that works with gravity in the the airflow to get movement horizontally or down.

I edited the second passage so I can type a little less. It has the same ideas as the original.

Actually the 4 seam fastball has a higher rotation rate of backspin

then it would have more movement?

faster rotation = more movement
more seams = more movement

To put it in more basic terms: instead of thinking that rotation makes the ball move, think of how it displaces air. If a ball spins through the air and creates different air pressures, the ball moves to the lower pressure. The 4-seam fastball creates more pressure below the ball so it would not break down, left, or right. It’ll just go straight (however, when tilted, it changes the air pressure created by the ball and could move left or right. That’s a cutter).

All-in-all, the faster the 4-seam spins, the greater the difference in air pressure (forcing the ball to stay up longer), the straighter it will go.

Hope that helps.

The more rotation there is there is the quicker the pitch will be. But as soon the rotation of the ball is at a different angle that’s when the ball will move.

The four seam is the fastest and straightest pitch you can throw. A two seam is typically 2-4 mph slower than the four seam, but it will have tailing and sometimes sinking movement depending on the arm angle.