This page and it's associated built-in Javascript is designed to help the analyst quickly and efficiently extract necessary data from online diagrams of armor piercing projectiles such as their length, diameter and L/D ratios; important as such diagrams often do not have measurements written out on them and they are often necessary for armor penetration calculations.

To start, simply load an image file (CHOOSE FILE) from your PC. Use the Rotation buttons below the "CHOOSE FILE" button to get your image as de-skewed as possible; then enter the known diameter of the shell in the input field.

Finally, click on the "1.) Measure Main Diameter" button to start the process; then on #2, #3 and #4 in that order.