Whoa! Never knew that. I could see that as an impediment to wide-spread adoption. In school in the fifties, we always learned Colt was the innovator of interchangeable parts, but we never learned about this design shortcoming. How did he get his company off the ground with this design?
That was a limitation of the Patterson model and some of the other early models. By the time of the revisions of the Walkers and 47 and 49 pocket pistols, they could be loaded from the front of the cylinder. . . Still a slow process. Some smaller ones lacked "loading levers" used to press the bullet into the cylinder and still essentially required the gun's barrel to be removed to do it easily.