Dr. Harold Vaughn is undeniably one of the greatest research scientists of the past century. In 1998, he authored a landmark book entitled Rifle Accuracy Facts that covers a ton of primary research Vaughn conducted with the same rigor as the most professional laboratories in the world. The subtitle of that book is, “A distinguished scientist’s lifelong pursuit of the secrets of “Extreme rifle accuracy.” It is frankly one of the best books I’ve ever read on the subject of precision rifles, and one I still pull out to reference often – and I’ve read a stack of them!
Dr. Vaughn was a highly decorated research scientist from Sandia National Laboratories (SNL) who arguably contributed as much to our understanding of modern weapons and ballistics as any other figure in history. Vaughn is considered the “grandfather” of aeroballistics/flight mechanics of nuclear missiles, he pioneered the use of computers to obtain complete trajectory calculations for bombs, shells, rockets, reentry vehicles, etc., and he provided many other ground-breaking solutions to problems that left others baffled.
Lucky for us, Harold Vaughn was also an avid rifle shooter. After retiring from SNL, he was determined to answer the nagging question: Why do some rifles shoot much better than others? Vaughn said his “natural curiosity as an engineer and professional ballistician” drove him to conduct countless experiments in an attempt to fully understand the details of what happens in that brief window between when the trigger breaks and the bullet hits the target. Harold wasn’t satisfied even if all the bullets went in one hole … until he knew why. His research is absolutely fascinating and still very insightful and relevant today.
Unfortunately, Dr. Vaughn passed away in 2003. His book, Rifle Accuracy Facts, was originally published by Precision Shooting Magazine, which has gone out of business and the book is no longer in print. Because of that it isn’t readily available, and I’ve seen used copies sell for several hundred dollars! One of my friends who is deep into ballistic research knew “Harry”, as he called him, and has so much respect for his work. He told me he tried to talk to Vaughn’s family about purchasing the rights to the book, just to try to get it republished so the shooting community would have access to all his amazing research. Unfortunately, that hasn’t come to fruition.
Since the book is no longer in print and there is virtually no way for most people to get a copy, I will say that I’ve noticed that there are complete PDF versions published a few places online. I’m in no way associated with these websites, but I’ll share a couple links, because I do wish more people could have a chance to read Dr. Vaughn’s work.
Download Complete PDF Versions of Rifle Accuracy Facts:
- https://archive.org/details/RifleAccuracyFactsFullV1.0FirstFullScan
- https://www.docdroid.net/6hLepTY/rifle-accuracy-facts-full-v11.pdf
- https://www.scribd.com/document/360161729/Rifle-Accuracy-Facts-Harold-R-Vaughn
Finally, here are a couple of other resources that share more information about who Dr. Harold Vaughn was from his book, Rifle Accuracy Facts:
From The Back Cover of Rifle Accuracy Facts
A highly-decorated veteran of World War II’s Pacific Theatre, Harold Vaughn flew one hundred combat missions in P-47’s and P-5l’s and lived to look back on his experiences. After the war he joined Sandia National Laboratories in New Mexico, duly progressed to Supervisor of the Aeroballistics Division, and occupied that lofty position until his retirement in 1986. As supervisor of the division, be provided technical direction to a large staff of scientists.
In his spare time in recent years, Mr. Vaughn has been increasingly bothered by the question that has haunted American rifle shooters back to Revolutionary times … why do some rifles shoot much better than others? With determination of a type to be expected in a man with his background, Harold Vaughn set out to find plausible answers to this enigma. After years of experimenting and testing, you, the reader, now hold answers to questions that earlier generations of riflemen sought but could never attain.
From “About The Author” by Jack E. Jackson in Rifle Accuracy Facts
Harold Roy Vaughn was born in 1924 at the family farm a few miles south of Amarillo, Texas. After graduating from high school, he entered Amarillo Junior College in September, 1941, to study engineering.
He volunteered for the Army Air Corps Reserve (the beginning of the US Air Force) in June, 1942, and reported for duty in February, 1943. He flew 100 combat missions in P-47’s and P-51 ‘s from bases in New Guinea, Morotai, the Philippines, China, and Okinawa and was awarded the Air Medal with four Oak Leaf clusters and seven battle stars during his tour of duty. Colonel Charles Lindbergh flew several missions with Harold’s squadron as a civilian technical consultant to demonstrate how to obtain more aircraft range with optimum throttle and propeller speed settings. Harold returned to civilian life in January, I 946, and to Amarillo Junior College to finish the last semester of his sophomore year in engineering. During the summer of 1946, he entered the University of Colorado and received a BS in aerodynamics in 1948 and a MS in aerodynamics in 1949. He worked at the NACA (now NASA) Ames Research Laboratory, Moffett Field, California, from September 1949 to September 1951, where he conducted research on the aerodynamics of swept wings. In September 1951 he joined Sandia National Laboratories, Albuquerque, New Mexico as a staff member in the Aerodynamics Department. He was promoted to Supervisor, Aeroballistics Division in July 1959, a position he held until his retirement from Sandia National Laboratories (SNL) in 1986. This division provided the flight dynamics and the aerodynamic research and development and design for nuclear weapons. As supervisor of this division, he provided technical direction to a large staff of scientists.
Harold is considered the “grandfather” of the aeroballistics/flight mechanics technology base for nuclear ordnance at SNL. In the early I 950’s he recognized the ballistics problem of roll-pitch resonance of tactical bombs. He mathematically modeled the motion and then recommended a fix of fin tabs, canted fins, or spin rockets to spin through the bomb pitch frequency, thereby avoiding divergent pitch/yaw motion. These solutions have been used on all nuclear bombs and sounding rocket systems at SNL. He was responsible for the aerodynamic design of a rocket boosted Mach 5 test vehicle to test baro-fuzing probes in 1957. He pioneered the use of computers in the field to calculate launcher settings to minimize dispersion for the several hundred unguided instrumentation rockets launched at Kauai and Johnston Island during the 1958 and 1962 high altitude nuclear tests. He was responsible for the aerodynamic design of the 14,000 pound Strypi rocket system which was developed in the fall of 1962 to boost a 560 kilogram nuclear warhead to an altitude of 150 kilometers at Johnston Island for the Checkmate event of the Dominic high altitude test series. He developed and published theories for analyzing reentry vehicle motion and dispersion, including the effects of roll resonance, heat shield thermal distortion, aerodynamic or inertial asymmetries, spinup, and exoatmospheric nuclear attack. One of these publications is extensively quoted in F. J. Regan’s 1984 book Re-Entry Vehicle Dynamics. He developed and published a theory for the ballistic match (same impact point for identical launch condi tions) of nuclear and high explosive warhead artillery shells. This theory identified the required matching inertial parameters which enabled the Los Alamos National Laboratory and the Lawrence Livermore National Laboratories to design the nuclear warheads. He developed and published a comprehensive theory for calculating forces and moments on spinning shells. In the early 1980’s he published the numerical solution of the Navies-Stokes equations to predict the fluid motion inside a spinning nutating cylinder using the Cray super-computer. This first theoretical solution explained the flight instabilities of spin-stabilized, liquid-filled artillery shells. He also initiated many other programs such as (1) pioneering the use of computers to obtain complete trajectory calculations for bombs, shells, rockets, reentry vehicles, etc. (2) working with the SQL Field Test organization to develop a miniaturized 3-axis system for use on-board test vehicles to measure angular motion which is telemeter to a ground station and (3) conceiving of and developing the SQL Flight Simulation Laboratory.
Harold received the 1974 American Institute of Aeronautics and Astronautics Mechanics and Control of Flight Award. The award was “for ~is fundamental contributions to the understanding of the flight mechanics of reentry vehicles, rockets, bombs and shells, together with his innovations in their aerodynamic design for stability and minimum dispersion in transonic flight.” He received the Outstanding Civilian Service Award from the U. S. Department of the Army in 1976 for solving a serious ballistics problem with the M422 shell. Movement of parts inside the shell caused a large undamped nutational motion that increased the drag, thereby markedly decreasing the range. He received the Department of Energy “Award of Excellence” from Major General W. W. Hoover in 1982 for significant contributions to the nuclear weapons program for “Ballistic Similitude” of artillery shells.
Harold has many hobbies – big game hunting, oil painting, photography, electronics, skiing, fly fishing, gardening, ultralight aircraft, and precision shooting. His advancing years have made some of these hobbies fond memories but he still pursues the less physically demanding ones. Behind his desk in his spacious study hangs a majestic elk, originally number 13 in the book. A grand slam on sheep adorns the fireplace wall. Numerous other big game trophies decorate the study. A small, well equipped photographic darkroom opens off of his study. A short hallway leads to a shop at the back of his garage that contains a Clausing lathe and vertical mill plus numerous other pieces of equipment. This well equipped shop is constantly used for projects related to precision shooting.