I am also fairly new to the 300 RUM, and have been doing some load development, I am using 210gr Berger VLD, with H1000 standard seating depth of 3.60 (from Berger) Rem brass, and CCI 250 primers
here is 87 g H1000, 5 shots at 100yds (pulled 1 out), avg vel- 2852fps
and here is 88gr of H1000, 5 shots, 100yds (pulled 1 out here as well) avg vel- 2913 fps
Maybe not the best in the world but a petty good place to start I figure, probably will play with the seating depth a little, and try 0.5gr incraments as well. Hope this helps.