Officials say no decision has been made whether Major Gregory McMillion will be court-martialed or instead subject to non-judicial disciplinary action.
They say the suspected contraband at Eglin also includes other rifles, Iraqi uniforms, knives and bayonets.
The items were found when equipment was unpacked after about 130 troops returned in November.
McMillion is part of the wing's 728th Air Control Squadron, which operated ground radar equipment for seven months at Baghdad International Airport.
He is accused of violating five articles of the Uniform Code of Military Justice.