If you're using hodgdon data look at the oal for each bullet. Same weight but different oal, bullet profile, seating depth etc. the 3.3 is already near max pressure in the configuration tested so if you go to 4.8 with the hap the pressure will be drastically higher than at 4.8 in the fmj using the data provided. Don't look at 4 data points like they are related they're not. It's 2 sets of 2 points.