Hi Scott,
Here are some pics of the catalog pages I mentioned.

Also here is a pic of two types of screw key padlocks I have similar to the one you show. The paldock on the left appears to be exactly like yours and uses the same type of key. The one on the right is smaller (about ½ size) and uses a more fancy key. I think this is just like the one shown in the french 1901 catalog. An interesting feature of this smaller lock is that it is self-locking, it can be snaped shut after the screw key is removed.

I’m not entirely sure why the newer Deny catalog calls these artillary padlocks, but perhaps at one time they had a millitary application. I know there are industrial applications also, because I have seen many of these on ebay stamped with SNCF (acronym for the French National Railroad).