Gav and Dave, the Slow Mo Guys, are back to compare the muzzle velocity of four popular rounds: 9mm, .45 ACP, 7.62x39mm, .416 Barrett. (The .416 would have been a .50 BMG, but they’re filming in California, so they’ve made due with what they can obtain legally).
Everyone knows the .45 ACP is the slowest of the bunch with a muzzle velocity around 900 fps and the .416 Barrett should come in first place somewhere above 3,000 fps. The difference in these velocities is staggering, but its virtually undetectable by the naked eye.
Using their V2511 ultra-slow motion camera, the guys can record at 100,000 frames per second to demonstrate just how much a difference a few thousand fps can make.
At that frame rate the AK-47’s barrel harmonics are clearly visible. When a rifle is fired a rapid increase in pressure makes the barrel vibrate and resonate almost like a whip. The resulting harmonic oscillation affects the projectile’s ballistics, which affects the accuracy of the shot. For this reason, the barrel should never be resting on a sand bag, rail, or other support when a weapon is fired.
See the difference in bullet speed like never before with the video below.