I don't know of a way.
This is the reason I use iParts as a "Factory"... setting to the new iPart, SaveAs new file, delete the Table and finally the Mass over ride in iProperties.
I had to work around this same issue a couple months back.
To make it work I had to create several custom materials in the iPart factory that, when assigned to a configuration, gave me the correct estimated mass.
Then in the table I had to assign each configuration its corresponding material.
Obviously you don't want to have to do this for very big tables.
Here is a old post, from the attachement I introudced solutuion to solve iPart mass issue, hope it's helpful.
Quality Assurance Team