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33 Comments on “Bowling Ball Hardness | Legal and Illegal | Why Does Hardness Matter?”

  1. Ron,

    This video lives up to the “Creating the Difference” name. Love it. Lots of good information and well thought out explanation of the subject and why it matters. No feelings and conjecture just facts. I’d love to hear more of David’s thoughts and experience on the matter. I’m sure he’s “seen it all” so to speak. Im curious how the different colors and additives affect the measured hardness of the ball. I saw him pointing at the two different points on the cover of that particular purple hammer. Was he saying that the parts with more pearl measure differently than the other parts?

    1. Yes we touched on the color hardness in the blog. He was extremely helpful in explaining things.

  2. This is a better test than the previous video, but I expected it as a teaser for the full video. This is a much better explanation and example

  3. Very enjoyable and informative video!

    I do have a question about the hardness of purple hammers decreasing. Do they really decrease that significantly over time? Going from low-mid 70s down to mid 60s seems like a huge decrease.

    1. Yes the USBC has some data that would indicate that happens. It’s also backed up by the balls we had made by EBI.

  4. So here’s a good question:
    Since a softer ball slows down more and has a larger footprint, thus creating more miss area. Wouldn’t surfacing a ball to a rough grit, no matter whether it’s reactive or urethane, also have a similar affect?

    1. @Bobby Burton I know that… but in theory they cause the same thing on the ball.

      A softer ball has a larger footprint, which means that more of the cover touches the lane. This causes the ball to slow down at a faster rate than a harder ball.

      Likewise, a ball with more surface slows down faster than a ball with less surface.

    2. Sorta but not exactly surface creates earlier hook but softer creates even hook. So the biggest difference between the two happens at the backend of the lane.

    3. @Ronald Hickland Jr I see.

      Is there a significant difference in hardness between a pearl ball and a solid ball?

  5. What a great analysis. I love the way the purple hammer looks, and I love that it’s a rather unique ball in the market. It’s a shame that some of the older batches of the ball have to be banned, but so be it.

  6. One experiment I would like to see the difference in how a urethane ball effects the breakdown of the pattern vs reactive. I think you would need to use a variety of different balls/surfaces on different patterns/volumes with a scientific approach. One thing we are having to learn is how to combat or take advantage of other people throwing urethane while trying to use reactive. On some sport patterns, breaking the pattern down with urethane then switching to reactive can be advantageous, while on most house shots it’s really trying to find a way to combat it. Some scientific data on this would go a long way. Also knowing which types of urethane balls have more of an effect on the breakdown than others.

  7. Love the details, transparency and science here. Thank you for sharing. Would be interesting to see how you chemically altered the balls to get the to soften like you did.

    1. That’s the only part we left out. It wouldn’t be ethical to show how to create an illegal ball.

  8. Wow, he tested 4 spectre bowling bowls and the lowest reading he got was 72.7 on the first spectre. I understand that technically it doesn’t pass USBC standards at 73D hardness, but is .3 hardness going to make that big of a difference in competition? It is up to the individual bowler to throw the ball correctly to get the right movement out of it. I would love to test and see the hardness of my spectre was!

    1. With the +/-2 wouldn’t those spectre tested still be legal??? Also does anyone think that usbc rule changes about 5 yrs ago on rg for cores and ra for covers make it hard for companies to create a difference in bowling balls thus hurting ball sales. This making the ball companies push the limits of hardness rules for ball sales???

  9. Great stuff ! I wish you would ask the gentleman a few things since he came there. Have you figured the rate at which the purple hammer gets softer ? As in 1 point per 50 games, or 1 point per 3 months. Is it only related to time passed, or how many games it has been used ?

  10. Looking at that label on the video title still brought me back to the old days for just a minute. I remember the pain and agony we used to go through to find the pins on those early 2 piece balls, before someone had the brilliant idea to color the pin lol. Finding the pins on any Urethane ball was a real treat, guys used to use magnifying glasses and others would use dust from the workbench and spread it around the label, sometimes that would highlight the outline of the pin lol. I would give anything to go back to those days of drilling Blue Hammers, Black Turbos, Red Pearl Hammers etc, those were good times! 🙂

  11. Here are my thoughts, why isn’t this process automated, from my reading the error rate +/-2. That’s way too large of an error rate for me to be comfortable, I think if it was .02 and not 2, that would be a huge difference. Anyone know if the humidity levels have an effect? I also tend to think a 5 degree temp range for the test is way to large. It was definitely much clearer when you started throwing the ball! Thank you guys for taking the time to make this!

  12. The bigger question now after seeing several shots with both a legal and illegal ball is how much prize money has been awarded the last 5+ years to bowlers who were less accurate in a tournament than others from amateur to PBA level competition. It’s no secret why so many PBA bowlers won with Purple Hammer. This should make all bowlers irritated beyond belief and the fact it took the USBC/PBA like 5+ years to even address this when Sean Rash and other legit bowlers have been complaining about it. 💯

  13. It looked like you tested some spectres as well. Will there be a part 2 on what you found concerning their hardness?

  14. This was the best video and blog article CTD ever made!
    Question 1: Doesn’t a lower grit on a legal Purple make it perform like a softer Purple?
    Question 2: Why don’t urethane balls made in the 80’s get softer? My Grey Rhino after 30 years still measures 76.

    1. 1. No because surface makes the ball hook earlier. Softer makes it hook more even. The biggest difference between the two is noticed on the backend of the lane.
      2. The softer it is to start the more “uncured” it is so it’s easier to become even softer. The harder it is the more cured. Most balls get harder over time due to continually curing.

    2. @Ronald Hickland Jr Question 3: Is it just Purples that get so soft so fast?
      I noticed my brand new Brunswick Purple that I have been using since July of 2021 is already super smooth and soft and spongy feeling and hooks way more than it did when I first got it. Even if I hit it with a 1000 grit pad it still looks like it is polished or smooth in texture and I can make a mark in it with my fingernail. What is causing this rapid softening?

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