p_ham
Well-known member
That article used a .223 for the test cartridge. It uses faster powders at a much higher pressure and only around 25gr of powder, burnout often happens around the 18-22" mark.20”…
Know of several instances where people have cut barrels 1” at a time and 18-21” shows the greatest velocity and little or no change to point of impact.
The latest one I’d seen on guns and ammo showed an increase actually of velocity going from 26” to 20”.
Barrel Length vs. Velocity - Guns and Ammo
I'm destroying a perfectly good barrel in the name of science. And not just a perfectly good barrel — an expensive one."How much velocity do I lose if I shorten the barrel on my AR?"The answer ranges fromwww.gunsandammo.com
.308 sized cartridges also do well in the same barrel length range. Again, at higher pressure.
Since this is a low pressure round, around 43,500psi it needs more barrel and a bit slower powder to get the most out of it especially when the bullet weight goes up.