Colorado’s recently approved gun control laws are being challenged by a delegation of sheriffs who say the laws are unconstitutional.

The two laws ban ammunition magazines that hold more than 15 rounds and require background checks for all private gun sales and transfers.

All but 10 of the state's 64 county sheriffs signed on to the suit. In the complaint, the sheriffs allege the new laws, which go into effect July 1, severely restrict citizens' constitutional right to own and bear arms.

The sheriffs, who in Colorado are elected, also complained that they were operating under tight budgets and did not have the money or manpower to enforce the new laws.

Joining the sheriffs in the lawsuit are a number of gun-rights organizations and a disabled gun owners group, who say that magazine limits would restrict their ability to defend themselves in violation of the Americans with Disabilities Act, which bars discrimination against the disabled.

Governor John Hickenlooper, who signed the bills into law, is named as the defendant in the lawsuit.