Cars, yup for a while, as well as machine tools (churchill) earthmoving equipment (birtley), they also owned ariel motorcycles and triumph motorcycles. Basically if it was made of metal, chances are bsa made it. Of course they employed thousands of skilled people, a very old fashioned notion, companies only employ robots and computers now.
I had a plain bsa side by side years ago, it was a good quality and good handling gun. The only fly in the ointment was the barrels were pitted. It had no engraving apart from BSA stamped on the sides of the action. I would like to know what haddoke held against them ? They weren't purdeys or H&H, but they probably allowed the ordinary working man a decent gun at a price he could afford.
