Well it depends what type of shrimp but most shrimp are light unless they have a thick shell or are fat. Most are 1-2 pounds.
1-2 pounds
That depends on the caliber. Different calibers are different sizes and weights.
Loaded or unloaded?
Technically I think It depends on how much can fit sometimes a lot can fit in one cup and sometimes very little so it depends theres not really an exact amount