There are so many different types of slugs and different types of chokes available today... Certain combinations of slug and choke might not be a good idea..

HOWEVER, regular foster type rifled slugs are perfectly safe to fire through any 1940 era full choke, be it a Win M12, an Ithaca 37, a Remington M31 or any other barrel made from around 1912 to whenever with a fixed choke...

Just be sure to use the "old fashion" foster style lead slugs, like Remington Sluggers, or the equivalent from Winchester, Federal, and others...