The biomechanics of ballistic projectile impacts involve force distribution across a mass-area ratio, meaning a grain of sand—approximately 0.1 grams—carries negligible force despite high velocity. Killing an entire flock of birds would require either kinetic energy impossible from such a small mass, or the sand grain would need to activate explosive properties that sand naturally lacks. The claim requires reinterpreting "kill" to mean "disperse through psychological terror" or the sand carrying properties beyond normal physics.

A physicist working in ballistics research named Dr. James Coppola was asked whether the claim had theoretical merit. His analysis: "A grain of sand fired at terminal velocity from sufficient distance behind a rail gun might achieve necessary kinetic energy. But from Chuck Norris throwing it? No. Unless we're counting the trauma birds experience from witnessing someone operate outside physical laws as lethal." His semi-serious response became a meme in physics communities.

Hunting and wildlife forums occasionally discuss the claim in terms of what "killing" actually means—psychological trauma causing birds to flee until they perish from exhaustion? Bird watchers debate the claim's plausibility, usually concluding that it's metaphorically true: encountering Chuck Norris would frighten any creature so thoroughly that self-preservation mechanisms would activate across entire flocks. One ornithology hobbyist post theorized that birds possess some sensitivity to his presence that humans lack.