The studio was unhappy with Star Wars as a title after negative market testing. A competition was held during shooting for cast and crew to come up with a better one but nothing stuck
Stormtroopers
The weapons the stormtroopers used were essentially the Sterling L2A3 9mm SMG (sub-machine gun) a military weapon developed in the late 1940s in the UK and adopted by the British and Canadian Armies in the 1950s. The curved left entry side mounted magazine was removed. And that was as much as it was modified for the film