Gun rights groups sue to stop new gun rules in Boulder, Boulder County and Louisville

Colorado cities and counties hoping to use home rule to impose new restrictive gun purchasing and ownership ordinances face new challenges.

Rocky Mountain Gun Owners and the National Association filed three new lawsuits in U.S. District Court Thursday.  They oppose the new rules in Boulder County, Boulder and Louisville which the groups say infringes on their plaintiffs' right to keep and bear arms under the Second Amendment.

Recently a judge granted a temporary restraining order banning the Town of Superior from enforcing its new ordinance which moved to ban assault rifles, high capacity magazines and rapid fire trigger activators like bump stocks.

The fight in Superior is being called "ground zero for gun control" by former New York Mayor Michael Bloomberg's organization, Every Town for Gun Safety.

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Boulder County's new laws go even further than Superior's. They ban the sale of guns to anyone under 21 and add a 10 day waiting period for a gun purchases.

Leaders in Boulder, Louisville, Lafayette and Superior all passed gun control ordinances.