Savysplace,
There are others here more familiar with French proof laws, than I. By the German proof law, a normal chamber would be designated by a 16 in a circle. A nonstandard chamber ( ie. 2 3/4" or 3.00") would need the chamber length added. When the normal chamber is designated, there is no need for a 65, since it is understood. I suspect the French law is the same, except they may use a Diamond, rather than a circle.
Mike