                                                        United States Court of Appeals
                                                                 Fifth Circuit

                                                              FILED
               IN THE UNITED STATES COURT OF APPEALS       August 17, 2004
                       FOR THE FIFTH CIRCUIT
                                                       Charles R. Fulbruge III
                                                               Clerk

                              No. 04-40372
                          Conference Calendar



BERNARD VINCENT MONTGOMERY,

                                      Petitioner-Appellant,

versus

UNITED STATES SENTENCING COMMISSION,

                                      Respondent-Appellee.

                         --------------------
            Appeal from the United States District Court
                  for the Eastern District of Texas
                     USDC No. 1:04-CV-2-MAC-WCR
                         --------------------

Before HIGGINBOTHAM, DAVIS, and PICKERING, Circuit Judges.

PER CURIAM:*

     Bernard Vincent Montgomery, federal inmate #53653-146,

appeals the district court’s dismissal of his 28 U.S.C. § 2241

petition.   Montgomery asserts that his 28 U.S.C. § 2241 petition

challenged the manner in which his sentence was being executed

and that the district court erred by construing the petition

under 28 U.S.C. § 2255.    He contends that the application of the

Sentencing Guidelines in the determination of his sentence

constituted a violation of the Ex Post Facto Clause.


     *
       Pursuant to 5TH CIR. R. 47.5, the court has determined that
this opinion should not be published and is not precedent except
under the limited circumstances set forth in 5TH CIR. R. 47.5.4.
                           No. 04-40372
                                -2-

     Section 2255, 28 U.S.C., is used to collaterally attack a

federal conviction and sentence based on errors that occurred at

trial or sentencing.   Jeffers v. Chandler, 253 F.3d 827, 830 (5th

Cir. 2001).   Section 2241, 28 U.S.C., is used generally to

challenge the manner in which a sentence is executed.    Jeffers,

253 F.3d at 830.   Montgomery’s 28 U.S.C. § 2241 petition

challenged the use of the Sentencing Guidelines, an alleged error

that occurred at sentencing, and was construed properly under 28

U.S.C. § 2255.   See Jeffers, 253 F.3d at 830.

     The district court did not err in concluding that

Montgomery’s petition did not meet the requirements of the 28

U.S.C. § 2255 savings clause.    See Jeffers, 253 F.3d at 830-31.

Montgomery has not shown that his claims were “‘based on a

retroactively applicable Supreme Court decision which establishes

that [he] may have been convicted of a nonexistent offense.’”

Id. at 830 (citation omitted).   Accordingly, the judgment of the

district court is AFFIRMED.
