Those drop in kits to turn an AR-15 into a .22lr sort of follow the idea.
I think the biggest bottleneck for this concept in private use is the rifle and pistol rounds having to share diameter, and aside from the 5.56 and .22lr, there isn’t much common overlap I can think of. 7.62x25mm isn’t exactly falling off the shelves.
Those drop in kits to turn an AR-15 into a .22lr sort of follow the idea.
I think the biggest bottleneck for this concept in private use is the rifle and pistol rounds having to share diameter, and aside from the 5.56 and .22lr, there isn’t much common overlap I can think of. 7.62x25mm isn’t exactly falling off the shelves.