Omar Martin Ramirez was found guilty by a jury of being an illegal alien and convicted felon in possession of a firearm, in violation of 18 U.S.C. § 922(g)(1) and (5)(A); he was acquitted of possessing a short shotgun. The district court 1 sentenced him to concurrent 52-month prison terms and 3-year supervised release terms. On appeal, Ramirez argues the district court improperly calculated his base offense level based on possession of a short shotgun, see U.S.S.G. § 2K2.1(a)(3), when that fact was not charged as an element in the counts of conviction or proved beyond a reasonable doubt, and the jury found him not guilty of possessing such a gun.

We conclude the district court did not err in sentencing Ramirez. The court had authority to impose any sentence not exceeding 120 months imprisonment. See 18 U.S.C. § 924(a)(2) (10-year maximum prison term for violating 18 U.S.C. § 922(g)); United States v. Aguayo-Delgado, 220 F.3d 926, 933 (8th Cir.) (judge-found fact may permissibly alter defendant’s sentence within statutory range for offense simpliciter), ce rt. denied, 531 U.S. 1026, 121 S.Ct. 600, 148 L.Ed.2d 513 (2000). Further, the court was free to consider conduct underlying the count on which Ramirez was acquitted. See U.S.S.G. § lB1.3(a)(l)(A) (base offense level determined on basis of all acts and omissions committed by defendant during commission of offense of conviction).

Accordingly, we affirm.