I still don't understand, even with pictures wink

Ed Lowry, ballistician and the director of research at Olin-Winchester, spark shadowgraphs. See "The Effect of a Shotstring" American Rifleman, November 1979.
The shells were likely the Winchester/Western Mark 5 with the polyethylene shot collar and fibre wads introduced 1961



Another images, the source of which I can't find. It appears to be 1 1/4 oz. Steel 5s = 304 pellets; possibly Kent Teal Steel at 1350 fps.

Cylinder at 30 yds looks like full at 50. The exact constriction is also unknown



I recall a discussion about coloring pellets; front, middle and back and taking images in flight as to change in location? Would probably need inside and outside also.

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