it loads easier with the CHinese Drums than the Beta C mag, U100
drums and the Russian 75 rd drum. However, once the chinese drum is
loaded, you need to crank the back crank to get the spring
tension/
Its quite effecctive way to load and do not get a soar thumb!
If I can recall the U100 drum has to be loaded one at a time from
the top and it requires a machine to lpoad the full 100rds.
The chinese drums comes in both 75 rd and 100 rd!
DaveC