I was having a discussion with some people I know about the bowling pin league, and invariably somebody says "21 feet? That's easy!". I show them the score sheets that prove that it is NOT easy, but most remain unconvinced. I therefore engaged in a little mathematics to explain.The pins are of the dimesnions shown to the right. The shooting occurs at a distance of 21 feet away. In order to successfully hit a pin, the allowable lateral trigonometric tangent of angular variation is the radius of the pin divided by the 21 foot distance, or:
As you can see, the resulting angle suggests that if a shooter is off by a mere 0.28 degrees, he misses the pin completely. Even a marginal hit, however, may only succeed in spinning the pin and leaving it laying on the tabletop. This means that a shooter must be within 0.2 degrees of perfect to have a reasonable chance of dislodging the pin. In the vertical direction, there is more forgiveness, but variation that exceeds 0.77 degrees vartically will also result in a clean miss.
With only tenths of a degree of allowable variation, this competition is certianly not easy. Even with my 4 MOA dot C-more sight, the dot appears to be approximately 0.29 inches wide on the 2.54 inch wide pin. Iron sight shooters will have even more difficulty gaging the lateral accuracy.
If you still doubt, show up March 1 at Multi-Lakes and give it a go.
