Hi Mate,
I did get a work around for this problem a few years ago and its worth a go if you have any grief from the french, I don't have the paperwork in front of me so am digging deep into my elderly failing memory, but the gist is.
Many Police /Customs don't really know what the euro laws are and have stated to me that military calibre's aren't allowed.....they are. The detail that you need to chase is within the Vienna Convention, this is a Euro wide agreement for any shooter who owns a firearm licence. If you are not staying in another country for not longer than 3 months ( I think) the host nation will honour the calibre's conditions etc as prescribed on your own FAC plus euro licence. If you stay longer, then you need to import and you are then subject to the host nation laws.
That is it in a nutshell so best of luck.