Other posters are correct, H 110 and 296 are for near to full power loads.

With a 275gr lead bullet I would start with 20 grains and work up till you find an accurate load.

I would not "waste" good 275gr cast bullets for plinking, I would get some 240 cast and load them over 7 to 9gr of Unique, deending on how much recoil you want in your plinking loads.