Thanks for the help - I did find a couple of "armor ignoring" weapons - they seem a little less common in early game than piratez, and changes were made since Poet's game that caused my confusion.
Another possible bug (running current code, I think, so it might be relevant):
Gtk:ERROR:../../../../gtk/gtkiconhelper.c:494:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /org/gtk/libgtk/icons/48x48/status/image-missing.png: Unrecognized image file format (gdk-pixbuf-error-quark, 3)
Aborted (core dumped)
OpenXcom has crashed: There is already TileEngine movingUnit
This was during "nightmare in antartica" or some such, first mission I played like this. Happened on enemy turn with some pink humanoid monster. Let me know if I can provide more details.