So they do buffed .45 Automatic by reducing 1 resource, which is okay. But also with a new name, like why? I don't really see a problem if they just buff .45 Automatic instead.

I don't really appreciate card games eliminating old cards like this, although I can see .45 Automatic are not eliminated totally in Arkham, because you can take them both if you need four .45 Automatic. But still, this gun will replace .45 Automatic completely.