For the second time in eight weeks, Alliant Techsystems is laying off workers at its Federal Cartridge ammunition plant in Anoka because of the end of an orders backlog, officials announced Thursday.

About 70 to 80 workers will be affected. In November, 40 to 50 workers were let go. Federal Cartridge will have about 900 workers after the job cuts.

The cutbacks are somewhat of a blow to Alliant Techsystems, which has prided itself on steady employment and sales growth. Federal Cartridge makes police and hunting ammunition sold through Wal-Mart, sporting goods stores and to dozens of police departments around the country.

The company hired 150 workers in Anoka about a year ago to clear a backlog of orders for pistol and small rifle ammunition. Alliant Techsystems spokeswoman Amanda Covington said the company has cleared the backlog, and with hunting seasons ending, Alliant is facing reduced demand.

Eden Prairie-based Alliant Techsystems has about 17,000 employees and $4.5 billion in annual sales.

The company has transformed itself from a small defense subcontractor when it was spun off from Honeywell in 1990 into a major defense, ammunition and aerospace contractor. It now builds missiles, precision-guided weaponry, satellite parts, sensors, rocket boosters, commercial aircraft parts and training ammunition for the U.S. Army.

Sales in Alliant's armament division jumped 25 percent to $864 million for the first six months of its 2009 fiscal year. Covington said ammunition sales are still growing, particularly orders from police. She declined to provide details.

Federal Cartridge is the latest Minnesota company to announce layoffs in the midst of a difficult economy. It joins 3M Co., Imation, Graco, Tennant, Pentair, Hutchinson Technology, Andersen Corp. and Deluxe Corp., which together have cut more than 8,160 jobs in recent months.

Dee DePass • 612-673-7725