The Army risks wasting as much as $1.8 billion developing a replacement for the M4 carbine that it may not need, according to the Pentagon’s inspector general.

The carbine replacement program is one the Army and Pentagon “may want to re-evaluate,” as the service is “seeking to acquire more rifles during a time when their total force structure will be reduced,” Lynne Halbrooks, principal deputy inspector general, said in a statement provided today to a House committee. The Pentagon plans to reduce Army ground forces to 490,000 by 2017 from about 560,000 in 2011…

The carbine replacement is among programs Halbrooks highlighted as having questionable value in the statement to the House Committee on Oversight and Government Reform…

The inspector general’s efforts are focused on deficiencies in financial management, acquisition processes, contract management, readiness, information technology security and equipping and training Iraq and Afghan security forces, according to a staff memo prepared for lawmakers.

The Army carbine program is an example of decisions the Pentagon and military services face in culling savings from the projected $27 billion expected to be spent in fiscal 2012 on major acquisition programs…

Halbrooks’s statement summarized areas of potential savings in financial and contract management completed by her agency such as the finding in 2011 of spare parts overpricing by Boeing and Sikorsky Aircraft to support the helicopter maintenance at the Army’s Corpus Christi depot in Texas.

Those overcharges, which were previously disclosed, are cases in which the Army “did not effectively use” existing inventory before buying overpriced parts from the contractors, Halbrooks wrote…

The Pentagon doesn’t manage its purchases up to the standards of, say, Home Depot.