"Springfield 1911" works fine.
I went to Google's home page, selected the "shopping" link, and typed "Springfield 1911" in the search blank. Got a bunch of hits, didn't check the count. Worked fine for several searches yesterday. I did clear my cache to try and insure that I am getting up-to-date info.
From what I can tell firearms searches on Google Shopping work exactly as they should.
As far as I am concerned, this is a closed issue.