Caliber debates have the sound of a magic button search. As it is, the defensive use of handgun performance is in a smaller lane: reliability, controllability, and relatively sufficient penetration to hit vital structure. The current bullet design has narrowed the difference between the common service calibers, but it...

The AR-15 is a product frequently being handled like a plug-and-play appliance: everything fits together, the labels are what they say, and the rest is internet trivia. The real benefit of the platform the standardization may also conceal the fact that the system is sensitive to tolerances, gas timing,...