Cloning database tables

If I have a database (SQL) with identical schemas on two seperate computers, how can I clone the contents of certain tables?
I already have a mechanism (in WCF) whereby I can send text between the computers.
Currently I have a fairly clumsy mechanism where the data is all loaded into a dataset, the XML of that dataset is sent over to the other machine, and then a fairly long parsing routine builds sql statements that re-insert the data on the other machine.
The key here is that the primary keys of the tables cannot be changed, they must be the same on both machines.
I bow to your superior knowledge for guidance...