The company says it plans to continue its normal business operations during its restructuring.
The company is struggling with more than $350m (Â£225m) in debt, as well as waning sales.
Colt's fortunes were hurt by the loss of a contract in 2013 to supply the US army with its M4 assault rifle.
Keith Maib, the company's chief restructuring officer, said: "Colt remains open for business and our team will continue to be sharply focused on delivering for our customers and being a good commercial partner to our vendors and suppliers".
Colt has been plagued by financial problems in recent months.
Last November Colt took out a $70m loan from Morgan Stanley to help make an interest payment.
But last month it missed a $10m interest payment.
Last year sales of its sports rifles and handguns fell 30%.
The company has a long US history, known for making American firearms for more than 150 years.
The company previously filed for bankruptcy protection in 1992, emerging again two years later.
Connecticut-based gun maker Colt Defense has filed for bankruptcy protection, as it grapples with a heavy debt load.