Not sure exactly what the story is with that 54cal but when we look at the enfield... You need to look at the entire cartridge.
The US self expanding bullet was loaded without paper around it. The paper cartridge was just a way to hold powder and bullet.
They had serious issues with accuracy and fouling. And are slower to load since you need to remove the bullet from the paper.
And there is only one thickness of paper used. Trying to balance durability and easy of opening. So the simplified version use dduring the war was also often a bit hard to open without tearing the paper and spilling some power.
But they where very easy to make and the paper thickness and quality did not really matter that much.
The brits made the bullets for the P1853 like this. And they are loaded with the creased paper.
And the csa imported them by the millions.
They where way way superior in all ways... save one.
Better accuracy, much easier to load and no to little issue with fouling.
But production is the downside.
The cartridge are more complex to make and require high quality paper. Down to 1000th of an inch.
It use different thicknesses of paper. Allowing for high durability for most of the cylinder, but a much thinner top so it is very easy to just tear open with your fingers.
The csa ordonnance department tried to make their own, but never managed to get it to work properly.
Even despite importing paper for it.
Here Brett is firing 4 round in a minute with them. and explain why they are so good.
oh, and if you have 4 minutes, take a look at this one.
This present one way to look at the british cartridge compared to the us one... obviously made for fun.