git svn for svn snapshots?

I'm using a native git repository for my development, but to work with
a certain build system, the sources need to be in svn. So I want to
keep using git and then just periodically push a snapshot to an svn
repo to work with this build system.

Is there a way to do this with git svn? I tried just adding the svn
remote to my config file, doing a fetch, and using set tree, but it
said there were no upstream revisions. The svn repository is huge and
my stuff just goes into one folder in there (one that I just created
with svn mkdir).