Jack O'Conner liked the bronze points, I don't but this is based on limited use. He used his classic load of 60 grains of surplus H4831 for the 130 grain bullets, Speer lists 58 grains of IMR 4831 as max so cross reference and work up loads. R26 is ideal for the 150s and works with 130s too go to the Speer or Hodgdon sites for the recipes.
Anything between 4350 and H1000 will work well for that range of bullets. I used R22 but am switching to R16 and R26 once those loads are used up. R23 is an option and may be more available than R26.
The Grand Slams are good bullets, I like the older dual core design which yours probably are. Have not used the 270 solid base bullets but I would section one to see if it is the thick core type or not. The early ones had the thin jacket like the Ballistic tips before they were beefed up. They were fairly frangible, I accidentally hit a doe in the spine too far back and what was left of the back straps would barely make a sandwich. The bullet did take out a pretty good section of spine lengthwise but only the base of the bullet remained.
