This topic comes up pretty regularly. The earliest work I've seen rigorously documenting the effect of runout was a pair of articles by Jacobsen and Abbatiello in American Rifleman in 1960. Abbatiello was a highpower competitor who calculated how much "bullet tilt" affected groups and documented it on target. He discussed his findings with Jacobson who was an engineer with Frankford Arsenal. Jacobson used the FA resources to more rigorously put Abbatiello's work to the test.

Here's an earlier thread where I provided a bit more detail;
https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/15556310/1

Mule Deer, did you ever run down a copy of those articles, or do you still need a scan? They truly are cool articles worthy of the read.

Last edited by ChrisF; 02/19/24.