I've recently been shooting 3.5 gr. of W231 with a Fed. 100 primer under an HSM 158-gr. LRN bullet from my old Colt Trooper in .38 Spcl. They'll easily stay well under an inch at 7 yards. I would think a medium charge of Bullseye would also do well; 3 grains may be the ticket.
US Navy Distinguished Marksman Badge 153
Former US Navy & Palma Rifle Team Member
NRA High Power Master & Long Range High Master
NRA Smallbore Prone Master