Given that, if I were you, I’d keep one or two G18 mags in the car “just in case”, maybe just with FMJ. Lots of additional capacity for not much cost/space.
Just an idea . . .
Agree but If you can get back to your car it should be for the rifle or shotgun.... but yes my gear bag in the truck has spare pistol mags as well.... if ya buy those 33 round G18 mags make SURE they are glock factory......NOT shear brand....