# BB Ballistic Coefficients

Quote of the Day

A serious problem in planning against American doctrine is that the Americans do not read their manuals, nor do they feel any obligation to follow their doctrine.

— Soviet observation during the Cold War (link).

Figure 1: Steel BBs with copper or zinc jackets. (Wikipedia)

A number of years ago, I was asked by a father to assist him and his son with a science project that involved calculating the ballistic coefficient of a BB gun projectile. I provide this father-son duo with the required calculations (documented here) and the answer I obtained seemed reasonable.

Another reader has recently asked further questions on these calculations and I thought I would take a quick look at how the ballistic coefficient of various BBs varies from one manufacturer to another.

This was a quick task that involves scraping some BB data from a web page (here), parse a bit of HTML, and plotting the data. The task is straight forward and the calculations are documented in this Excel workbook (here). This task was a good exercise in using Power Query and Excel to extract data from a web page without tables.

Figure 2 shows the distribution of BBs documented on the previously mentioned web page. My earlier calculations, assuming nominal BB parameters, showed the ballistic coefficient to be ~0.0145, which is near the mode of the chart in Figure 2.

Figure 2: Distribution of BB Ballistic Coefficients from 80 different BBs.

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