I've named a couple of my guns, but not many. I don't know why, but it only seems appropriate for certain ones...
I have a customized T/C Renegade with a .54 roundball barrel that I shot through a golf club handle offhand at 25 yards with the first two rounds I ever shot out of the gun - that's "Girlfriend." Another .54 Renegade I picked up a few years later looked like she could have been stocked from the same tree - that's "Sister."
My Jackie Brown Carolina Smoothbore is named "Caroline."
I have a custom-built Hawken named "Pappy." Long story there...
That's really about it for named guns, although I have several others that I use a lot, including two TVM's.
In my case, it either strikes me or it doesn't. Not all of my guns will have names, but I do think it's a fun aspect of muzzleloading that so many of us have names for our guns. I've never thought of naming a modern gun...
Spot