Production-security plans help sustain unique French calibers

How would the Allies resupply the French fleet's unusual gun calibers?

Factories could measure the French equipment, adapt existing production, and use material already shared by France. Changing main-battery calibers would be a major project.

The French had already shared material with Britain to help British factories produce supporting parts if French production suffered bombing damage. Factories could also measure French equipment and adapt items already in production. Sustaining the unusual calibers would be difficult, but worthwhile in this assessment. Converting the French heavy-gun ships to 14-inch weapons is another possibility, though it would be a major project.