Smyth Busters: A Heavy Caliber AR-15 Requires a Heavier Buffer
This video debunks the common myth that AR-15 platforms chambered in heavier calibers like .300 Blackout, .350 Legend, or .450 Bushmaster inherently require a heavier buffer. The hosts explain that the AR-15's gas system is designed for standard pressure and cycling with a 3 oz. buffer. They contrast this with blowback-operated pistol caliber uppers (.450 Bushmaster, .40 S&W, 9mm Luger) and AR-308 platforms which do necessitate heavier buffers due to different operating mechanisms or larger components. While heavy buffers can sometimes be used for tuning short barrels, slowing cyclic rates on full-auto, or reducing felt recoil (with gas flow adjustments), they are generally not needed for standard AR-15 heavy caliber conversions.








