boolean problems

[commador]

Hello all. I am in the middle of creating an FN SCAR-L and its all coming together nicely, but Im having trouble with the difference boolean operator. I am creating the indentation where the ****ing handle is in the body of the rifle, and using a simple cube to do this. When I select the body mesh and then select the difference operator, the cube is picked and the problems begin. I used the difference operator successfully multiple times to create the picatinny rails but its not working at all now. What happens is, XSI becomes non responsive and my CPU usage is at 100%. Its not a memory problem because (according to the task-manager) its well within its limits. So, why is this happening when I know its worked before?

The mesh has right now about 1800 polygons, if that helps in determining the problem.