Barrel Size, Is Bigger Always Better? An In-Depth Look
Many times, when I or other wood bat manufacturers are receiving an order from a customer, a series of requests comes up. Can you make it lighter? Can you make it stronger? Can you make the barrel bigger?
The idea that these three traits can be modified separately is a carryover from usage of composite or alloy hollow bats. Most of these bats are at maximum barrel size, modified by weight with dense inserts and have durability/power directly correlating to the strength of the material.
With wood, this is not the case. These three qualities are all interconnected. Wood bats are solid instruments. They have flex, but little trampoline effect. A wood bat’s quality is a game of trade-offs, and this includes barrel size, but NOT for the reason you might think. Today we will be focusing on just this aspect.
When a person requests a bigger barrel, typically they do not want to change the overall weight of the bat dramatically. In that case, what they are doing is putting more mass at the end of the bat compared to the handle. The farther away the majority of the weight, the heavier the bat will feel. This means a slower and less controlled swing, but more power delivered to the ball. This is called endload. In the elite class of power hitters, endloaded bats are commonplace. Their high strength allows them to overcome the issues with control and speed, in order to deliver more power to the ball.
When it comes to players not in the elite level though, the perception of a bigger barrel is not a matter of weight or power. It’s the idea that like a tennis racquet, it makes it easier to hit the ball, in which case they are only partially correct. The differences in a small barrel and large barrel are so minute that they cannot be relied upon. I will be tackling this notion in its entirety and give the facts hereof.

The biggest offender of barrel size in baseball history has to be Heinie Groh, whose bat became legendary for its awkward shape.
The idea “bigger barrel = easier hit” comes from the striking visual of the bat, viewed similarly to a flat surface to have a better chance of making contact, but unfortunately, bats are round.
This means that the extra area a larger barrel gives you is on an awkwardly angled surface, usually leading to a foul ball, whereas on a smaller barreled bat, this would’ve been a strike. This difference is demonstrated below, where the ball passes by the small barreled bat untouched or barely tipped, whereas the big barreled bat hits straight into the air or ground.

Mind you, launch angle is roughly equal to the angle at which the ball comes in + 2x the angle of contact from the center. This is discounting spin and viscoelasticity, both of which benefit smaller barrels, but for simplicity, let’s discount those and call this a foul ball with a 126 degree launch angle.
The ability to foul ball a possible strike is a situational benefit. First off, it is only necessary on a two-strike count. Otherwise, it has no definitive difference to a strike other than mental support. There is also a limit to this, as a foul tip is essentially the same as a strike, unless the catcher drops the ball, an exception I’ve seen happen ONCE. A foul tip is when you just BARELY graze the ball, and it lands right in the catcher’s glove. This puts a severe limit on the benefit of that extra barrel.
A foul ball can actually be a detriment to the game. A foul ball on a strike hurts the possibility of a successful stolen base for runners on-base, because the ball is considered dead. Taking the maximum diameter of a barrel allowed by MLB and NCAA leagues (2.625”) and comparing the extra foul ball range to that of a softball bat (2.25” smaller than even the densest baseball turn models) gives you an extra 0.1875” of hitting room on either side. This is the thickness of a mildly overgrown fingernail tip.

This is the extent of the benefits of a bigger barrel in the most extreme of differences. At Pommel Bats, we offer a 2.25” diameter turn model for little league bats and ultra-high-density big-league bats, but most of our turn models range from 2.35” to 2.55”. The actual differences from the average barrel diameter (2.45”) are the width of a nickel, roughly .0875 inches. Put a nickel on your wood bat and judge whether a bigger barrel is a significant benefit.
To put this benefit in a statistic, Jose Altuve has a ratio of foul tips to whiffs + tips of 12/199, or roughly 6% and he’s known as a “fighter” of the pitch count.

Just look at that barrel! It’s bigger than his forearm. Credit to Flickr: apardavila for the photo.
Joey Gallo led the league in strikeouts this year. He uses a very large barrel. Unfortunately, the ratio of foul balls to save the count compared to total strikes is 124/1072 or 11.5% of all strike possibilities whereas his rate of unproductive foul contact (foul balls not on 2 strike count and tips compared to strikes – called strikes) is at 38%. He swung the bat 1068 times this year and of those swings, 38% were whiffs and 35% were foul tips or foul balls. 45% of all hits, including foul balls, were within the preferred launch angle, indicating that the instances of his larger barrel being an important factor were very rare. I estimate that given his weak contact percentage of 6.6%, the number of times he actually employed the aid of a big barrel was 2%. Joey Gallo would HAND you or I our behinds in a baseball game, so he is by no means a bad player. This just shows the benefits of a large barrel is not significant, even on the biggest stage.
Funny enough, the highest pitch at-bat was in 2018 with Brandon Belt, who uses a smaller barreled bat as seen below:

Image courtesy of Jeffjeff08
The next effect is the difference on “hitting angles”. This includes launch angle and pull angle. As for launch angle (the angle that a ball comes off the bat) is a matter of the angle the ball comes in (roughly -8 degrees in most amateur leagues for fastballs), the swing plane (angle of the bat as you hit the ball) as well the offset from a perfectly aligned hit (distance from the “center” of the bat to the edge). A perfectly square hit would have 0 difference in offset, negating the difference in barrel size. Keep in mind, the area at which 2 round objects collide is a single point (neglecting collision squish, which has little effect on this principle). If you tend to uppercut or chop at the ball, firstly, speak with a hitting coach, secondly, offset will have less effect on your hitting, therefore neither does barrel diameter for launch angle.
This is a picture of a diagram pulled from Ted William’s instruction on hitting, being taught by many hitting schools today

If we were to diagram this perfect swing as the ball makes contact with the bat, this would be the effect at the moment of contact:

A perfectly aligned hit may have maximum velocity, but only an 8-degree launch angle, meaning a line out or ground ball to the infield or base hit to the gap. A typical line drive has a launch angle of 10-25 degrees. Let’s go with a 20-degree launch angle as an average. This means that an aligned swing plane would need a barrel offset of roughly 6 degrees. If you were to swing a 2.25” diameter bat, it would actually be a larger angle because the difference in barrel to ball size is greater. How much is this difference at a 6 degree offset at the most extreme? .4202 degrees. You cannot even see this difference on a diagram, but this is the basis of our comparison. For a certain linear offset from perfect alignment, smaller barreled bats increase launch angle faster. Meaning as you stray from perfect alignment, the launch angle on a smaller barrel increases faster. This sounds like a huge detriment, but the actual effect is so minor, it’s unnoticeable

For home runs, launch angle and exit velocity is essential. A typical home run has a launch angle of 25-35 degrees with the average being 30. An offset of roughly 11 degrees would be needed with a big barrel bat. Taking the same principle as before, the difference in launch angle at this significance is 2 degrees.

This is still in home runs range. Remember, we’re still comparing a massive soda bottle on a stick to our 2.25” softball bat, so usually, this difference is even smaller. This means that the only times that a big-barreled bat would exclusively give you a home run would be when the offset is 12-13 degrees. BUT HOLD ON! Home runs are mainly dictated by launch angle AND exit velocity. This secondary factor will become more important later on in our topic.
As for any offset above this range, it will be a fly-out anyways, until it becomes a foul ball.
AH! Remember what we said about smaller barrels increasing offset angle faster? This is where big barrels become a hindrance for launch angle. Whereas the big barreled bat is getting you in a pop-up, the small barreled bat is getting you a foul ball. A foul ball is arguably better than a pop-up. I know that sac flies exist, and a foul ball pop-up can be an out, but the rate at which this happens is insignificant.
Jose Altuve had 145 fly balls, 6 being sac flies this year. This is less than 5%. The argument to this is that pop-ups and fly balls can become hits, usually at a rate of 1 or 2%, whereas a foul ball is another pitch count with a possible out, also a 1-2% rate (side note, a foul ball can be a live ball if the fielder drops the ball while standing in fair territory).
Even so, a foul ball pop-up is not subject to the infield fly rule and players can tag up on a foul pop-up. This is an arguable advantage when the catcher/fielder is an extra 50-60 ft away with his back turned away, working similar in nature to a sac bunt/fly. This happened a few months ago with Kolten Wong scoring on a foul pop-up, where home plate was left abandoned.
Kolten Wong makes a heads up play, scores on an infield popout – 8/21/21
In addition to this, increasing the contact angle high enough gets to the point where the ball simply flies into the stands or line drives into the backnet, waking up the sleepy/drunk fans in the stands. I remember on my second anniversary with my girlfriend, we went to a Marlins vs Dodgers game, picking our seats with the explicit goal of catching a foul ball. There must have been 30 of these fliers, and ALL of them landed one section next to us; it was mildly disappointing.
I argue that a foul ball is better than a pop-up because it gives the batter another chance, and wears down the pitcher. At worst, this is an even trade and the offset of a big barrel popup to a small barrel foul ball is significant, a whole 6 degrees. This difference can visually be seen.

The last factor we’ll touch on is the effect on pull angle or horizontal pull. The effect on pull angle is a measurement of timing and swing angle. Considering angular velocity of an amateur level swing and pitch as well as the .1875” delay between a small and big barrel, the difference in pull of a ball is .53 degrees. If we measure ball flight at this .53 degree difference, the difference in pull at 400 feet out is a difference of 3.7 feet to the batter’s side. So not very significant at all. This difference shrinks as pitch and swing speed increase. This is displayed by this calculated graph below, created on desmos.

So, we mentioned the limited benefits of a bigger barrel; we mentioned the differences in angles between large and small barrels as well as situational and arguable benefits, but we haven’t even touched on the exclusive benefits of smaller barrels.
This is where things get juicy.
As mentioned, a smaller barrel can actually help you situationally to get strikes instead of foul balls for stolen bases and get foul balls instead of pop-ups to have another chance at productive contact and extend the pitch count of a pitcher.
In addition to this, a smaller barrel means less volume on the bat. This means a higher density wood can be used to reach the same weight. Density is a function of weight per volume. Reduce the volume and maintain weight, density goes up. The benefits of a higher density wood are enhanced strength, and in turn, durability, a common issue in modern-day baseball.
A higher density wood also provides more power to the ball by reducing deformation, which absorbs energy that would’ve been transferred to the ball. Players often say that higher density baseball bats sound like gunshots when making contact with a ball. This is because the energy is being transferred instead of lost to bat deformation. This means higher exit velocities. The exact measured differences in exit velocity will be measured in a future experiment, but it may be significant enough to even negate the power loss from the mass removed in the barrel.
Typically, a player will think of a bat’s swing weight as strictly the weight on a scale, but this is not the case. The bat is a rotating object. The distance of the mass to the hands matters much more than total mass. A 1-ounce string with a 20-ounce weight at the end will feel heavier than a 31oz baseball bat, even if the bat is 10 oz heavier on the scale.
Another benefit of a smaller barrel is the ability to create a better-balanced bat. By reducing the barrel size, you make the mass more evenly distributed. This will make the bat feel lighter and much easier to swing. Easier swing means more control. More control means better contact. Remember how we said that a bigger barrel gives you anywhere between .1875” and .08” of extra hitting area? Considering how much easier it is to swing a balanced bat over an end-loaded bat, it stands to reason that the ability to control the barrel placement can be much more beneficial to contact rates compared to the extra few nickels of area you have with a big barrel.
It must also be pointed out that better balanced bats promote better bat speed, also possibly negating the power loss from the mass removed in the barrel.
Javier Baez uses a large barrel and to this, he has the most foul-tips and whiffs in the league this year. He also would hand either one of us our behinds in a game. He is a very productive player. If he wasn’t, he wouldn’t be playing, but the effects of his style and choices for our case can be easily seen.
In the following pictures, I’ve placed a nickel on my personal bat (dubbed Mjolnir for being a 36oz, 33” birch bat of our CD2 turn model) with a barrel diameter of 2.5”. This means a nickel placed on the barrel actually surpasses MLB limits of barrel diameter. You can see the effect of maxing out barrels is actually VERY minor.


Now make no mistake, it is still quite possible to make an end-loaded/heavy swinging bat with a smaller barrel. This is done by either cranking up the density, getting a high-density turn model with endload, or increasing bat length. Pommel Bats offers smaller barreled models with endload and high-density wood if this is your goal.
As for the first option, most early sluggers used bats whose weight was actually greater than its length. Babe Ruth used a 42-ounce bat. Ty Cobb, one of the greatest hitters in history, used a 36-ounce bat. A balanced turn model like a 110 can have its swing weight increased to match that of a 243, but its scale weight would be 34 oz at 33” length.
In terms of Bat Length, as described in a video done by popular baseball bat aficionados “The Baseball Bat Bros” A long and light bat will still feel heavier than a short and heavy swinging bat.
I can throw all the science I want at you, but the proof is in the results. The MLB limits its barrel size to 2.625” and classic turn models like the 243 can be made with this barrel diameter. In recent years though, barrel diameters in professional settings have been getting smaller. More often, the largest barrel size you’ll see is around 2.45-2.5”.
Why don’t they max out the barrel size stat? Because they can get that same end-loaded feel by modifying the material density or the bat length. Bat length increases effective bat speed and makes hitting those outside sliders with 22” movement slightly easier. This is why even though a 33” bat is usually sold at 30 ounces (known as a drop -3), the most common drop in weight compared to length is 2-2.25 or less in the MLB and the most common length is 34” (as per NYTimes study https://www.nytimes.com/2013/07/30/sports/baseball/for-soriano-a-heavy-bat-has-always-felt-just-right.html)
What matters most is whether a player is satisfied with a bat and doing well on the field. If you are trying to get a good-looking bat that can pound the ball a mile, maybe a bigger barrel is good for you. I’d argue that a big fat barrel is ugly, almost like comparing a beautiful nimble sword to a heavy club. I’d also say that a little more balance and density will get you moonshots farther than you ever could with that big soda bottle on a stick and your batting average may go up. The choice is yours and preference is a personal variable, but what can be concluded here is that unlike some things, in this case, bigger isn’t always better.
Greetings, I am a physician, scientist, former ball player and baseball fan. I really enjoyed your article but this topic is begging for a randomized double blind study (most likely players will notice larger and smaller barrels unfortunately, however, if incrementally decreased this may reduce “unblinding”). The optimal baseball bat diameter needs to be studied and determined on the field. Perhaps we will discover very interesting findings at both extremes and MLB had it right all along, or, perhaps MLB hasn’t discovered the optimal diameter of a baseball bat. If you are interested in participating in such a study let me know. No matter what the results, this will be interesting and Im sure players/leagues/MLB would love to know the findings of such a study. I propose we start with a 3′ inch diameter barrels (approx same diameter as baseball and outside MLB allowance) and work our way to smaller barrels measuring batting averages, strikeouts, contact/swiff ratios, exit velocity, etc… You have my email address and I know a few custom bat makers who could assist in making wooden bats to our specs.
Very Respectfully
JHurley
Hello Jacob,
Thank you for your intuitive reply. I was actually planning on conducting an actual experiment for this but the issue has always been getting the bat characteristics equalized so that the only variable would be the one we want to test. With barrel size, volume goes up which means mass goes up or density goes down, both of which affect performance and mass distribution is thrown off course along with changes along the vibrational nodes. With wood as the material of choice, it would be impossible to conduct a true study. If you change the barrel size but equalize the Moment of Inertia, the flex properties change and density changes. I will speak to you in more detail on this, but I think there is a way to do this study but it’ll require building a bat solely for the study itself.
In the mean time, the best evidence we have is the largest experiment to date, the game of baseball. Treating the game of baseball as a method of natural selection and a continuous trial-error experiment, barrel sizes have been getting smaller and smaller over the last 50 years whereas MOI has been roughly the same ever since the 60s. This alone would be evidence of breaking the barrel size myth, but the issue with using historical trends is the confounding variable of regulation. In the 90s, players were using drug enhancement and upwards of 30% of the bats used are estimated to have been corked. Cupping the end of the bat had regulation changes and of course, ash has given way to maple and birch as the wood of choice. Not to mention the fact that in 2007, the MLB conducted a study on wood bat durability and implemented a regulation on wood density and grain straightness. All these are potential factors in why barrel sizes have changed. A noticeable drop in size has come after the 2007 study indicating that factors other than natural selection are in play. Nonetheless, larger barrel sizes are used for the same amount of Moment of Inertia in current bat selection yet not many players use those bats, which makes me think I’m on the right track