THE BOOK--Playing The Percentages In Baseball

It’s important to consider the supply chain here: balls used in August, 1967 would almost certainly have been made some time earlier than that, and it’s no guarantee that balls used in August, 1967 were made at a different time than those used in July, 1967. 

Nevertheless, it’s an interesting theory, I hope someone can shed more light on the manufacturing process and the supply chain / chain of custody from factory to ball field, so we can take this beyond speculation…

I think there is little doubt that the resiliency (and other characteristics) of the ball changes from time to time for whatever reasons, resulting in changes in HR rate and run scoring overall.  As I have mentioned many times, there are also many other things that do the same, not the least of which is the wildly varying pool of pitching and hitting talent from year to year…

I do not think Rawlings became the exclusive ball provider until 1977, but if they provided a large percentage of MLB balls, any changes to their balls could affect the overall rates.  HR rates changed drastically around 1977, and in 1987 when Rawlings shifted production from Haiti to Costa Rica.

#1 “and it’s no guarantee that balls used in August, 1967 were made at a different time than those used in July, 1967.”

Well, maufacturing is a continuous process.  I doubt all of the balls needed for a given season are made at one time, in one lot with an identical batch of raw material, and at the same factory.  I am sure balls are shipped on a lot by lot basis from the different factories.  It’s very likely balls used in August come from different lots than balls used earlier in the season.  You would be surprised at what can go wrong and go undetected (or even covered up if it is detected and shipped anyways). 

How little or how much variation there are in the finished balls from lot to lot depends on the factories QC, how well they control quality of incoming raw materials and manufacturing processes. 

I could see a scenario where new owners might want to seek lower cost raw materials, or shift more of their production to Puerto Rico, with fewer balls made in the US.  I doubt MLB had very tight QC on balls received, and the specs are so broad that balls within spec could have drastically different COR’s. 

If the weather was unusually humid across the country in the latter part of 1967 and 1968 then perhaps it was more of a conditioning problem, and nothing to do with manufacturing. But any changes to manufacturers ownership or changes in factories used should be suspect. 

#2 “wildly varying pool of pitching and hitting talent from year to year”.  I suppose there is evidence for that assertion, and a definition for “wildly varying”.

“#2 “wildly varying pool of pitching and hitting talent from year to year”.

I suppose there is evidence for that assertion, and a definition for “wildly varying”.

No, I’m just talking out of my ass like I usually do.  And you can make up your own definition of “wildly varying.”

http://www.insidethebook.com/ee/index.php/site/comments/why_you_really_need_to_know_the_league_changes_from_year_to_year/

Spalding owned Rawlings from the 1950s until they were forced to sell the company sometime in the 1960s due to a court antitrust ruling. I have seen a different dates on the sale.

Spalding was also the owner of the Reach company, which supplied the official AL baseballs before Rawlings. The shift was probably a case of Spalding phasing out the Reach brand and supporting the newer acquisition.

Reach actually manufactured the Spalding baseballs that were used in the National League. the only thing different was the cover, which (I believe) was applied by Spalding. I’ve seen differing info on this. Some sources say the only thing different was the logo that was stamped on the ball. However, in the 1930s Spalding changed the thickness of the cover on the NL ball a few times, and I think NL baseballs had higher seams. Both would indicate that Spalding was taking the “unfinished” baseballs and applying the entire cover. I don’t know what Spalding did after acquiring Rawlings. Did they keep the old Reach plant in operation or shift to Rawlings-made baseballs?