Barrel resonance.
Every barrel vibrates at a frequency when a bullet pass through it.
You want the bullet to leave the barrel at the crest of the sine wave on either side of that vibration.
Different bullet weights, different “ring” frequencies. And different barrels have different frequencies generated by the same bullet.
With a lightweight barrel you want the bullet and the barrel to match.
That is why all sniper barrels are very heavy bull barrels...they don’t change point of aim with that vibration.
Thanks...
Very interesting
I’m a radio guy and antennas and cable
length are tuned to the frequency.
Kind of a “ring.”
Now if I can figure out how I can make
my M1A work...can’t hit Crap with it!