I use some pretty hot Hornady 230 FMJ TC ammo to carry in my Sig P220 when guiding all summer. My logbook is over at a buddies house but I believe it was about 6.0 grains of N320. I think I had them at 1.260" OAL. Velocity was right at 1000 fps and was very controllable with my Sig. Be advised that this load is higher than max pressure listed with VV powders. I developed it very carefully and over the course of three years when I felt like messing with it. I also had similar velocities with 230 XTP and Montana Gold 230 JHP. I didn't have any Nosler to try but a friend who uses it in his Win Mag @ 1700 fps likes it a lot.
I remember being pretty happy with N340, too but it was harder to get, so I used N320. N350 was flashy and inconsistant for me.
I am using N340 behind the Speer GD 230 gr.. Their published data was wishful thinking. I was able to get 958 fps average with a "here not to be mentioned" increase without pressure signs. As a precaution I am using Starline +P cases.