From a 2.75 Ruger Security six, always have had good results form the Silvertips in 125grain.
I reload a hard-cast Keith bullet, 130grain, that the Six shoots accurately.
The hard-cast 130's are my choice for a woods gun round. Been using 4.5 grains of Hodgdon Clays. Found it minimizes the muzzle flash, but at the cost of running slower...[about 850-900fps] but with hard-cast, you don't need the bigger speeds, and so much is lost thru the short barrel. It's a good accurate load for the Six.