How Much Velocity Do You Really Lose Per Inch of Barrel? A 5.56 Chrono Study

Key points: Much Velocity Do You

• Single test barrel eliminates barrel-to-barrel variance entirely
• Ten-shot strings, three loads (55gr, 62gr, 77gr) at every length
• Average loss ran 25–40 fps per inch — but far from linear
• The steepest drop-off starts below 12.5 inches
• Raw chronograph CSV published for independent analysis

About this Ballistics Focu video

One barrel, cut down an inch at a time from 20 to 10.5, re-crowned at every step, with ten-shot chronograph strings at each length across three loads. It's the cleanest publicly available dataset on 5.56 velocity loss — no barrel-to-barrel variables, no extrapolation. The per-inch numbers are not what the forum wisdom says, and the knee in the curve lands where few expect it.

Transcript: Much Velocity Do