ammunition and each revolver. The average group size for the overall test was . Based on average group size, the winner was the Model 686, which shot an average group of across the brands of ammunition, with a standard deviation between ammunition types of . However, the Model 52, while shooting slightly larger groups at , was far more consistent across the brands, with a standard deviation of only , and was the most consistent performer of the test. However, if the ammunition was tuned to the gun, the clear winner was the Python, which averaged just with its favored brand of ammunition. The Python was also by far the pickiest, however, turning in the largest groups at averages with its least favorite brands, for a standard deviation of . Based on this test, answering the question "Which is the most accurate?" becomes a matter of opinion. The 686 shot the best average groups. However, as the Python showed the best performance with one brand of ammunition, it might be the best choice if that brand of ammunition were acceptable for the application in question. If a consistent supply of ammunition were a problem, then the 52 might be the best choice, since it showed the least sensitivity to differences in ammunition. Testing methodology As the goal of accurizing a firearm is to improve its accuracy, the way accuracy is measured becomes important. A firearm used primarily as a hunting weapon will need to be accurate on the first shot from a cold, clean barrel, while one used for target shooting may be allowed fouling shots before the first shot for record is fired. Issues of portability or restrictions of certain competitions may limit the alterations that can be made. In addition, every firearm is different, and processes that yield good results on one may not affect another. Another issue in measuring accuracy is the method by which the gun is secured for the test. The most accurate shooting position is a supported position, such as firing from a benchrest with the firearm well-supported by a shooting rest or sandbags; this eliminates much of the shooter's potential for error and will generally result in much smaller groups than firing from an unsupported position. Even for a firearm that is going to be shot offhand, accuracy testing from a machine rest will provide an idea of the ultimate attainable accuracy. Usability