Final answer:
Two common regulations for shotguns when hunting big game are restrictions on the barrel length and the type of gauge and ammunition used. These regulations are grounded in historical legislation like the 1934 National Firearms Act and are meant to ensure humane and ethical hunting practices.
Step-by-step explanation:
The two regulations for shotguns when hunting big game often involve restrictions on the types of firearms used and the manner in which they are used. Historically, major legislation such as the 1934 National Firearms Act, which included the prohibition of sawed-off shotguns, laid the groundwork for gun regulation in the US. This was done on the premise that such weapons did not serve the purpose of maintaining a "well regulated militia."
When it comes to hunting big game, state and federal regulations typically require the use of shotguns that have a barrel length over a certain measurement, often 18 inches, to prevent the use of illegally modified firearms. Additionally, there may be regulations regarding the gauges and ammunition types permissible for big game to ensure a humane kill, as well as overall ethical hunting practices such as not hunting young or overhunting beyond subsistence or population control needs.