Quote Originally Posted by Blah View Post
That seems awfully close to what a 7.62x51 would achieve with a 16" barrel.

The case is smaller than 7.62's as well, which would imply to me that it either runs at a much higher pressure, or is using some kind of special propellant.
It is around the same bullet weight and velocity, but the bullets have a better form factor and so they essentially have a much longer range. Tracer burnout will occur sooner.

As for how that velocity is achieved, for every 4% increase in powder you have a 1% increase in velocity. The rest of that energy is heat and blast. The smaller cartridge has less powder, but that is a good thing.

It runs at the same pressure as 7.62x51. And it is well adapted to short barrels. In fact, some cartridges shouldn't be run from long barrels. 7.62x39 is an example of a cartridge that gains almost nothing with a barrel over 12 inches long.