Now you got me curious.
Exactly what are you shooting at 4613 fps or did you accidently set the machine to cm/sec?
I am assuming that's one of the 17 cal varmint rounds or similar.
Ever calculate the RPS of those bullets going Mach 4?
That's a lot of rotational stress!
Bullet RPS = MV X 12/Twist Rate (in inches)
If you have a twist of 16 that's 3460 RPS!