Order

Timothy Johnson is before this court for a third time. We previously affirmed his convictions and sentence, see United States v. Johnson, 137 F.3d 970 (7th Cir. 1998), and the denial of his motion under 28 U.S.C. § 2255, see Johnson v. United States, No. 99-3762 (7th Cir. Jan. 5, 2001) (unpublished order). Last year he asked the district court to reduce his sentence under 18 U.S.C. § 3582(c), which permits this relief when the Sentencing Commission has authorized it by making a retroactive change in the Guidelines. Johnson contended that Amendment 599 applies to his situation. The district judge concluded, however, that although Amendment 599 is retroactive it is unrelated to Johnson’s sentence, so his motion was denied.

Johnson is serving concurrent sentences of 300 months for conspiring to distribute cocaine and 120 months for possessing a firearm despite a felony conviction. The felon-in-possession conviction, which rests on 18 U.S.C. § 922(g), has no effect on the total length of Johnson’s confinement. The 300-month sentence, calculated under U.S.S.G. § 2D1.1, includes an enhancement of two levels because Johnson possessed a weapon in connection with his drug dealing. See U.S.S.G. § 2Dl.l(b)(l). It is this enhancement that Johnson believes must be reexamined after Amendment 599.

*861Yet Amendment 599 did not change § 2D1.1. The amendment revised the commentary to U.S.S.G. § 2K2.4, which deals with sentences under 18 U.S.C. § 924(c). See generally United States v. Alcala, 352 F.3d 1153 (7th Cir. 2003); United States v. Howard, 352 F.3d 332 (7th Cir. 2003). Johnson has not been convicted of violating § 924(c), and the district judge did not employ § 2K2.4. Moreover, as we observed in Alcala and Howard, the point of Amendment 599 is to avoid double counting when a firearms conviction is coupled with a gun enhancement under some other provision. That can be a challenge under § 924(c), which requires consecutive sentences. Sentences under § 922(g), by contrast, can be concurrent, which avoids any problem. In assessing the 300-month sentence, the district court counted the weapon only once, and in precisely the way the Sentencing Commission authorized.

Affirmed