.... What???!!
Berger doesn't make a 115 RN... I said BARNES as a joke.... You aren't getting this, so I'll explain simply again.
You need to stop talking about bullet weights, as a thing.
Look at my previous post again. The same weight-class, same match style bullets, BIG difference in length.
Twist rate is for stability.
Stability is for a LENGTH, weight doesn't matter.
Weight is for choosing a date, or worrying about when they tone for a medical assist...
Here:
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
Length look-ups are on the left margin.
Again,
These fast twists limit how fast you can push bullets.
So bullet dependant, and depending upon how smooth your barrel is, here are the speed limits before the RPM destroys them.
8-twist - @ 3,200
7-twist - @ 2,800