So I make another run with the Ruger #1V .223. Tried 3 new bullets in it, all loaded with Varget. I also measured the twist at 1 in 9", not 1 in 8". That put me in a fairly bad mood, until I shot it:
The Berger OTM Tacticals are about .10" shorter than the Hornady 75gr Amax. The first 5 went into one hole. Not bad for a windy day. So...