@OP,

If you know the weight of your stock, your action, bottom metal, scope and mounts, you can use either the PacNor or the Lilja barrel weight calculator to "thumbnail" the weight of your barrel for all up weight. Either calculator will let you bit-twiddle length, contour and flutes to get close to your target weight. they may not be perfect. But, they will get you in the ball park. My recommendation would be to shoot a little UNDER your target weight since my builds always seem to come out a little heavier than planned.

Good luck with your project !

PacNor Calculator - Web page

Lilja Calculator Download - 3rd Bullet Down