Patton carried a Remington Model 1934 .380 under his jacket. In the movie he shoots at the German bomber strafing his HQ with this gun.
He also had an issue Colt 1903 .32 general’s model with four stars on each grip panel.
I think Patton used a Remington model 51 in .380 in addition to a general officers model 1908 pocket Colt in .380 also.