I found the 4.1 gr and the 4.3 gr (max) of N340 were both good shooting loads. Groups were a toss up. Loaded HST at 1.142 COAL with CCI 550 Sm pistol magnum primers.Yes, work up. My results are with Winchester brass, CCI No. 500 primers.
I think it may be a bit below max because Vihtavouri uses 1.142 COAL.
I got 1039 fps with a 13.0 SD at 42°F from a 16" PCC (25 shot average).
I don’t have an outdoor range where I can run them over my chronograph. Thank you AR for some nice components!