MSWord has a draw feature with a customizable grid.
I used it to draw some circular, square, and diamond shaped targets and then drew lines to show the grid. It makes it easy to compute the size of your groups and you can custom taylor your targets to your particular sights.
You can also use a text box and paste a photo in it for those "game" shots. Squirrels, and other small game can be made life size on a standard page. I use white construction paper and it leaves the same hole that target paper does.
I haven't purchased targets in twenty years. They are easier to fit in my notebook of records too.
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