I urge you to buy a hand priming tool and not use the Lee Loader to install primers. You will most likely pop one off from time to time, It's scary but not dangerous.
When whacking cases with the hammer, you must use a very firm surface. The floor beats a table top unless this table is a sturdy work bench. The 44 case is thick and somewhat difficult to size. You must use a good lube applied generously. Do you have a drill press? If so, you can use it to force the case into the size die. Harbor Freight has cheap presses that will do this easily. They are not reloading presses but will work for this task. Much less banging.