Chuck...what data source are you using?
The VV guide I have doesn't have a single load starting at 3.6 for N320 with a 124 gr projectile.
8,0 124 RN Rainier 29,0 1.142 N320 0,24 3.8 305 1000 0,27 4.1 326 1069
N330 0,27 4.2 324 1063 0,30 4.7 344 1129
N340 0,30 4.7 328 1077 0,33 5.1 351 1152
N350 0,34 5.2 340 1115 0,38 5.9 364 1196