3. Putting It Together

Anyway, let’s revisit our targets, Figure C-1, and see if we can make some observations on error sources and type.

Figure C-1
Accuracy and Precision


  • Target (a) shooter was both precise and accurate. This means the shooter has a pretty good handle on all the errors.
  • Target (b) indicates the presence of a systematic error: shots are consistently low and left. To compensate, the shooter can either adjust the gun sights (mechanical) or aim high and right (procedural).
  • Target (c) most likely results from a minimal experience shooter (error source: personal). On average the shooter has accurate results, but it’s achieved inefficiently. As the shooter gains experience, the efficiency increases and the pattern should begin to look more like (a).
  • Target (d) can result from all sorts of error sources and types: inexperienced shooter (personal), windy conditions (natural), gun sights off (instrumental), throw in a possible mistake or two, and so on.