Abstract: Measuring devices and systems for determining accuracy in marksmanship of one or more shots after firing a firearm at a point of aim are described. Each of the measuring devices includes a transparent sheet configured to be overlaid on the point of aim and the one or more shots, the transparent sheet having printed thereon: a plurality of vertical lines, a plurality of horizontal lines, the plurality of vertical lines and the plurality of horizontal lines forming a grid pattern, and a point of aim alignment marking, the point of aim alignment marking being located at a center of the grid pattern.