Well, 2 inchers weigh 5 grains a piece and 4 inchers weigh 12 grains a piece. I assume you are shooting stock nocks so they should weigh 7-12 grains. This gives you a grand total of about 394-399 with 2 inch vanes and 415-420 with 4's. Sorry I couldn't find the exact weight for the beeman nocks.