[fso301]

Furthermore, a lower ratio means an increased speed, so a twist rate of 1:7 will travel faster than one at 1:9, because it will complete a full rotation in only 7 inches compared to 9

I assume he means speed of rotation.

[MtnClimber]

And the longer the bullet, the faster the twist rate required to stabilize the bullet.

[GMMC0987]

The twist does effect velocity, but not by much.

http://bulletin.accurateshooter.com/2015/02/does-barrel-twist-rate-affect-muzzle-velocity-litz-test/