EDITOR’S FOREWORD: This article originally appeared in the 1965 Gun Digest annual, and was the first significant coverage of the then-new AR-15. Funny how politics is always involved in weapon procurement. Note the nonsense about “hydrostatic shock” and reports of 5.56mm nearly taking limbs off in Vietnam. This article has been edited and curated to fit this format, but the complete piece with more extensive testing can be found in our archives.