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                                                                  EXHIBIT 10.4.7

            SIXTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

         THIS SIXTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT
(hereinafter referred to as the "Amendment") executed as of the [ ] day of
September, 2003, by and among RANGE RESOURCES CORPORATION, a Delaware
corporation ("Borrower"), BANK ONE, NA, a national banking association ("Bank
One"), each of the financial institutions which is a party hereto (as evidenced
by the signature pages to this Amendment) or which may from time to time become
a party hereto pursuant to the provisions of Section 29 of the Credit Agreement
or any successor or assignee thereof (hereinafter collectively referred to as
"Lenders", and individually, "Lender"), Bank One, as Administrative Agent
("Agent"), Fleet National Bank, as Co-Documentation Agent, Fortis Capital Corp.,
as Co-Documentation Agent, JPMorgan Chase Bank, as Co-Syndication Agent, Credit
Lyonnais New York Branch, as Co-Syndication Agent, Banc One Capital Markets,
Inc., as Joint Lead Arranger and Joint Bookrunner and JPMorgan Securities, Inc.,
as Joint Lead Arranger and Joint Bookrunner. Capitalized terms used but not
defined in this Amendment have the meanings assigned to such terms in that
certain Amended and Restated Credit Agreement dated as of May 2, 2002, by and
among Borrower, Agent and Lenders (as amended, supplemented or otherwise
modified from time to time, the "Credit Agreement").

                                   WITNESSETH:

         WHEREAS, the Borrower has requested that the Agent and the Lenders
amend the Credit Agreement to increase the Hydrocarbon Borrowing Base to
$180,000,000; and Agent and the Lenders have agreed to do so on the terms and
conditions hereinafter set forth including eliminating any increase in the
Borrowing Base arising from the acquisition or redemption of Junior Securities;
and

         WHEREAS, as a result of the elimination of any increase in the
Hydrocarbon Borrowing Base arising from such acquisitions and redemptions it is
no longer necessary to distinguish between the Hydrocarbon Borrowing Base and
the Borrowing Base.

         NOW, THEREFORE, for and in consideration of the mutual covenants and
agreements herein contained and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged and confessed, the
Borrower, Agent and the Lenders, hereby agree as follows:

SECTION 1. AMENDMENTS TO CREDIT AGREEMENT. Subject to the satisfaction or waiver
in writing of each condition precedent set forth in Section 3 hereof, and in
reliance on the representations, warranties, covenants and agreements contained
in this Amendment, the Credit Agreement shall be amended in the manner provided
in this Section 1.

         1.1      DEFINITIONS. Section 1 of the Credit Agreement shall be and it
hereby is amended as follows:

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         (a) By amending the following definitions in their entirety to read as
follows:

         Borrowing Base shall mean, as of any date, the value assigned by the
Lenders from time to time to the Oil and Gas Properties pursuant to Section 7
hereof.

         Unscheduled Redeterminations means a redetermination of the Borrowing
Base made at any time other than on the dates set for the regular semi-annual
redetermination of the Borrowing Base which are made (A) at the request of
Borrower (but only once between Borrowing Base redeterminations), (B) at the
request of Super Majority Lenders (but only twice between Borrowing Base
redeterminations) or (C) upon the issuance of any Refinancing Securities,
provided, however, that (i) Super Majority Lenders may require an Unscheduled
Redetermination at any time it appears to Agent or Super Majority Lenders, in
the exercise of their reasonable discretion, that either (a) there has been a
material decrease in the value of the Oil and Gas Properties, or (b) an event
has occurred which is reasonably expected to have a Material Adverse Effect, or
(ii) Super Majority Lenders may require an Unscheduled Redetermination if
Borrower terminates any material agreements entered into in connection with a
Rate Management Transaction used by Lenders in determining the Borrowing Base or
if the counterparty to any such material agreement commences, or has commenced
against it any proceeding under any bankruptcy, insolvency or similar law now or
hereafter in effect.

         (b)      By deleting the definitions for "Hydrocarbon Borrowing Base",
"Increased Amount" and "Increase Limit" from such section.

         1.2      AMENDMENT TO BORROWING BASE. Section 7 of the Credit Agreement
shall be and it hereby is amended as follows:

         (a)      Section 7(a) of the Credit Agreement shall be and it hereby is
amended in its entirety to read as follows:

                  (a)      Initial Borrowing Base. As of April 1, 2003, the
         Borrowing Base shall be $170,000,000 and, subject to Section 7(b)
         hereof, as of October 1, 2003, the Borrowing Base shall be
         $180,000,000.

         (b)      Section 7(b) of the Credit Agreement shall be and it hereby is
amended in its entirety to read as follows:

                  (b)      Subsequent Determinations of Borrowing Base.
         Subsequent determinations of the Borrowing Base shall be made by the
         Lenders semi-annually on April 1 and October 1 of each year beginning
         April 1, 2004 or as Unscheduled Redeterminations. By March 1 each year,
         beginning March 1, 2004, Borrower shall furnish to the Lenders an
         engineering report in form and substance reasonably satisfactory to
         Agent prepared by an independent petroleum engineering firm acceptable
         to Agent, said engineering report to utilize economic and pricing
         parameters used by the Agent as established from time to time, together
         with such other information, reports and data concerning the value of
         the Oil and Gas Properties as Agent shall deem reasonably

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         necessary to determine the value of such Oil and Gas Properties. By
         September 1 of each year beginning September 1, 2004, or within thirty
         (30) days after either (i) receipt of notice from Agent that the
         Lenders require an Unscheduled Redetermination, or (ii) the Borrower
         gives notice to Agent of its desire to have an Unscheduled
         Redetermination performed, in each case the Borrower shall furnish to
         the Lenders an engineering report in form and substance reasonably
         satisfactory to Agent, said engineering report to utilize economic and
         pricing parameters used by the Agent as established from to time,
         together with such other information, reports and data concerning the
         value of such Oil and Gas Properties. Agent shall by written notice to
         the Borrower no later than April 1 and October 1 of each year, or
         within a reasonable time thereafter (herein called the "Determination
         Date"), notify the Borrower of the designation by the Lenders of the
         new Borrowing Base for the period beginning on such Determination Date
         and continuing until, but not including, the next Determination Date.
         If an Unscheduled Redetermination is to be made by the Lenders, the
         Agent shall notify the Borrower within a reasonable time after receipt
         of all requested information of the new Borrowing Base, and such new
         Borrowing Base shall continue until the next Determination Date. If the
         Borrower does not furnish all such information, reports and data by any
         date specified in this Section 7(b), unless such failure is reasonably
         determined by the Agent to be of no fault of the Borrower, the Lenders
         nonetheless designate the Borrowing Base at any amounts which the
         Lenders in their reasonable discretion determine and redesignate the
         Borrowing Base from time to time thereafter until the Lenders receive
         all such information, reports and data, whereupon the Lenders shall
         designate a new Borrowing Base as described above. The procedure for
         determining the Borrowing Base at each redetermination shall be that
         the Agent shall determine the Borrowing Base and submit the same to the
         Lenders. Increases in the Borrowing Base will require approval of all
         Lenders, but other reaffirmation or changes in the Borrowing Base will
         be subject to the approval of Required Lenders. If any redetermined
         Borrowing Base is not approved by Required Lenders within twenty (20)
         days after submission to the Lenders by the Agent, the Agent shall
         notify each of the Lenders that the proposed Borrowing Base has not
         been approved and each Lender will submit within ten (10) days
         thereafter its proposed Borrowing Base. The redetermined Borrowing Base
         shall be then determined (in all cases except those involving an
         increase of the Borrowing Base which requires approval of all Lenders)
         based upon the weighted arithmetic average of the proposed amounts
         submitted by each Lender, said proposals to be weighted according to
         each Lender's Commitment. Each Lender shall determine the amount of the
         Borrowing Base based upon the loan collateral value which such Lender
         in its sole discretion (using such methodology, assumptions and
         discount rates as such Lender customarily uses in assigning collateral
         value to oil and gas properties, oil and gas gathering systems, gas
         processing and plant operations) assigns to such Oil and Gas Properties
         of the Borrower at the time in question and based upon such other
         credit factors consistently applied (including, without limitation, the
         assets, liabilities, cash flow, business, properties, prospects,
         management and ownership of the Borrower and its affiliates) as such
         Lender customarily considers in evaluating similar oil and gas credits.
         If at any time any of the Oil and Gas Properties are sold, the
         Borrowing Base then in effect shall automatically be reduced by a sum
         equal to the amount of prepayment, if any,

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         required to be made pursuant to Section 12(r) hereof. It is expressly
         understood that the Lenders have no obligation to designate the
         Borrowing Base at any particular amounts, except in the exercise of
         their discretion, whether in relation to the Commitments or otherwise.
         Provided, however, that the Lenders shall not have the obligation to
         designate a Borrowing Base in an amount in excess of the Commitment.

         (c)      Section 7(c) of the Credit Agreement is hereby deleted from
the Credit Agreement.

         1.3      AMENDMENT TO UNUSED COMMITMENT FEE. Section 8(a) of the Credit
Agreement shall be and it hereby is amended in its entirety to read as follows:

         (a)      Unused Commitment Fee. The Borrower shall pay to Agent for the
ratable benefit of the Lenders an unused commitment fee (the "Unused Commitment
Fee") equivalent to the Unused Commitment Fee Rate times the daily average of
the sum of the (i) Borrowing Base minus Total Outstandings. Such Unused
Commitment Fee shall be calculated on the basis of a year consisting of 360
days. The Unused Commitment Fee shall be payable in arrears on the last day of
each calendar quarter beginning June 30, 2002 with the final fee payment due on
the Maturity Date for any period then ending for which the Unused Commitment Fee
shall not have been theretofore paid. In the event the Commitment terminates on
any date prior to the end of any such quarterly period, the Borrower shall pay
to the Agent for the ratable benefit of the Lenders, on the date of such
termination, the total Unused Commitment Fee due for the period in which such
termination occurs. If a date for payment of the Unused Commitment Fee shall be
other than a Business Day such payment shall be made on the next succeeding
Business Day.

         1.4      AMENDMENT TO AMENDMENTS. Clause (a) of the second sentence of
Section 24 of the Credit Agreement shall be and it hereby is amended in its
entirety to read as follows:

         (a) would increase the Borrowing Base,

         1.5      BORROWING BASE INCREASE FEE. The Borrowers shall pay to the
Agent, for the ratable benefit of the Lenders, a Borrowing Base increase fee
equal to one-quarter of one percent (.25%) of the amount of the $10,000,000
increase in the Borrowing Base from the amount in effect prior to the
effectiveness of this Amendment, which fee is due and payable on the date
hereof.

SECTION 2. REAFFIRMATION OF REPRESENTATIONS AND WARRANTIES. Except to the extent
its provisions are specifically amended, modified or superseded by this
Amendment, the representations, warranties and affirmative and negative
covenants of the Borrower contained in the Credit Agreement are incorporated
herein by reference for all purposes as if copied herein in full. The Borrower
hereby restates and reaffirms each and every term and provision of the Credit
Agreement, as amended, including, without limitation, all representations,
warranties and affirmative and negative covenants. Except to the extent its
provisions are specifically amended, modified or superseded by this Amendment,
the Credit Agreement, as amended, and all terms

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and provisions thereof shall remain in full force and effect, and the same in
all respects are confirmed and approved by the Borrower and the Lenders.

SECTION 3. CONDITIONS. The amendments to the Credit Agreement contained in
Section 1 of this Amendment shall be effective upon the satisfaction of each of
the conditions set forth in this Section 3.

         3.1      EXECUTION AND DELIVERY. The Borrower and each Guarantor shall
have executed and delivered this Amendment, and other required documents, all in
form and substance satisfactory to the Agent;

         3.2      REPRESENTATIONS AND WARRANTIES. The representations and
warranties of the Borrower under this Amendment are true and correct in all
material respects as of such date, as if then made (except to the extent that
such representations and warranties related solely to an earlier date);

         3.3      NO EVENT OF DEFAULT. No Event of Default shall have occurred
and be continuing nor shall any event have occurred or failed to occur which,
with the passage of time or service of notice, or both, would constitute an
Event of Default;

         3.4      PAYMENT OF BORROWING BASE INCREASE FEE. The Agent shall have
received from Borrower, for the ratable benefit of the Lenders, the Borrowing
Base increase fee required under Section 1.5 of this Amendment.

         3.5      OTHER DOCUMENTS. The Agent shall have received such other
instruments and documents incidental and appropriate to the transaction provided
for herein as the Agent or its counsel may reasonably request, and all such
documents shall be in form and substance satisfactory to the Agent;

         3.6      LEGAL MATTERS SATISFACTORY. All legal matters incident to the
consummation of the transactions contemplated hereby shall be reasonably
satisfactory to special counsel for the Agent retained at the expense of
Borrower.

SECTION 4. MISCELLANEOUS.

         4.1      ADDITIONAL REPRESENTATIONS AND WARRANTIES. Borrower hereby
represents and warrants that all factual information, if any, heretofore and
contemporaneously furnished by or on behalf of Borrower to Agent for purposes of
or in connection with this Amendment does not contain any untrue statement of a
material fact or omit to state any material fact necessary to keep the
statements contained herein or therein from being misleading. Each of the
foregoing representations and warranties shall constitute a representation and
warranty of Borrower made under the Credit Agreement, and it shall be an Event
of Default if any such representation and warranty shall prove to have been
incorrect or false in any material respect at the time given. Each of the
representations and warranties made under the Credit Agreement (including those

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made herein) shall survive and not be waived by the execution and delivery of
this Amendment or any investigation by Lenders.

         4.2      INDEMNIFICATION. The Borrower agrees to indemnify and hold
harmless the Lenders and their respective officers, employees, agents, attorneys
and representatives (singularly, an "Indemnified Party", and collectively, the
"Indemnified Parties") from and against any loss, cost, liability, damage or
expense (including the reasonable fees and out-of-pocket expenses of counsel to
the Lender, including all local counsel hired by such counsel) ("Claim")
incurred by the Lenders in investigating or preparing for, defending against, or
providing evidence, producing documents or taking any other action in respect of
any commenced or threatened litigation, administrative proceeding or
investigation under any federal securities law, federal or state environmental
law, or any other statute of any jurisdiction, or any regulation, or at common
law or otherwise, which is alleged to arise out of or is based upon any acts,
practices or omissions or alleged acts, practices or omissions of the Borrower
or its agents or arises in connection with the duties, obligations or
performance of the Indemnified Parties in negotiating, preparing, executing,
accepting, keeping, completing, countersigning, issuing, selling, delivering,
releasing, assigning, handling, certifying, processing or receiving or taking
any other action with respect to the Loan Documents and all documents, items and
materials contemplated thereby even if any of the foregoing arises out of an
Indemnified Party's ordinary negligence. The indemnity set forth herein shall be
in addition to any other obligations or liabilities of the Borrower to the
Lenders hereunder or at common law or otherwise, and shall survive any
termination of this Amendment, the expiration of the Loan and the payment of all
indebtedness of the Borrower to the Lenders hereunder and under the Notes,
provided that the Borrower shall have no obligation under this section to the
Lenders with respect to any of the foregoing arising out of the gross negligence
or willful misconduct of the Lenders. If any Claim is asserted against any
Indemnified Party, the Indemnified Party shall endeavor to notify the Borrower
of such Claim (but failure to do so shall not affect the indemnification herein
made except to the extent of the actual harm caused by such failure). The
Indemnified Party shall have the right to employ, at the Borrower's expense,
counsel of the Indemnified Parties' choosing and to control the defense of the
Claim. The Borrower may at its own expense also participate in the defense of
any Claim. Each Indemnified Party may employ separate counsel in connection with
any Claim to the extent such Indemnified Party believes it reasonably prudent to
protect such Indemnified Party. THE PARTIES INTEND FOR THE PROVISIONS OF THIS
SECTION TO APPLY TO AND PROTECT EACH INDEMNIFIED PARTY FROM THE CONSEQUENCES OF
STRICT LIABILITY IMPOSED OR THREATENED TO BE IMPOSED ON ANY INDEMNIFIED PARTY AS
WELL AS FROM THE CONSEQUENCES OF ITS OWN NEGLIGENCE, WHETHER OR NOT THAT
NEGLIGENCE IS THE SOLE, CONTRIBUTING, OR CONCURRING CAUSE OF ANY CLAIM, BUT NOT
FROM ANY PORTION OF SUCH CLAIM ARISING FROM THE GROSS NEGLIGENCE OR WILLFUL
MISCONDUCT OF ANY INDEMNIFIED PARTY.

         4.3      COUNTERPARTS. This Amendment may be executed in one or more
counterparts and by different parties hereto in separate counterparts each of
which when so executed and delivered shall be deemed an original, but all such
counterparts together shall constitute but one and the same instrument;
signature pages may be detached from multiple separate counterparts and attached
to a single counterpart so that all signature pages are physically attached to
the same

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document. However, this Amendment shall bind no party until Borrower, Agent and
Lenders have executed a counterpart. Facsimiles shall be effective as originals.

         4.4      WRITTEN CREDIT AGREEMENT. THE CREDIT AGREEMENT, AS AMENDED,
REPRESENTS THE FINAL AGREEMENT BETWEEN AND AMONG THE PARTIES AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS
OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN AND AMONG THE
PARTIES.

         4.5      NO IMPAIRMENT. Borrower acknowledges and agrees that the
renewal, extension and amendment of the Credit Agreement shall not be considered
a novation of account or new contract but that all existing rights, titles,
powers, and estates in favor of the Lenders constitute valid and existing
obligations in favor of the Lenders. Borrower confirms and agree that (a)
neither the execution of this Amendment nor any other Loan Document nor the
consummation of the transactions described herein and therein shall in any way
effect, impair or limit the covenants, liabilities, obligations and duties of
the Borrower under the Loan Documents and (b) the obligations evidenced and
secured by the Loan Documents continue in full force and effect.

                            [SIGNATURE PAGES FOLLOW]

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         IN WITNESS WHEREOF, the parties have caused this Sixth Amendment to
Credit Agreement to be duly executed as of the date first above written.

                                    BORROWER:

                                    RANGE RESOURCES CORPORATION
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    LENDERS:

                                    BANK ONE, NA, a national
                                    banking association (Main Office Chicago)
                                    as a Lender and Administrative Agent

                                    By:_________________________________________
                                    Name: Wm. Mark Cranmer
                                    Title: Director, Capital Markets

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                                    BANK OF SCOTLAND

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    JPMORGAN CHASE BANK

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    COMPASS BANK

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    CREDIT LYONNAIS NEW YORK BRANCH

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    FLEET NATIONAL BANK

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    FORTIS CAPITAL CORP.

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    NATEXIS BANQUES POPULAIRES

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    COMERICA BANK
                                    (successor by merger with
                                    Comerica Bank-Texas)

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                            CONSENT AND REAFFIRMATION

         The undersigned (each a "Guarantor") hereby (i) acknowledges receipt of
a copy of the foregoing Sixth Amendment to Amended and Restated Credit Agreement
(the "Sixth Amendment"); (ii) consents to Borrower's execution and delivery
thereof; (iii) agrees to be bound thereby; (iv) affirms that nothing contained
therein shall modify in any respect whatsoever its guaranty of the obligations
of the Borrower to Lenders pursuant to the terms of its Guaranty in favor of
Agent and the Lenders (the "Guaranty") and (v) reaffirms that the Guaranty is
and shall continue to remain in full force and effect. Although Guarantor has
been informed of the matters set forth herein and has acknowledged and agreed to
same, Guarantor understands that the Lenders have no obligation to inform
Guarantor of such matters in the future or to seek Guarantor's acknowledgment or
agreement to future amendments or waivers, and nothing herein shall create such
duty.

         IN WITNESS WHEREOF, the undersigned has executed this Consent and
Reaffirmation on and as of the date of the Sixth Amendment.

                                    GUARANTORS:

                                    RANGE ENERGY I, INC.
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    RANGE HOLDCO, INC.
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    RANGE PRODUCTION COMPANY
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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                                    RANGE ENERGY VENTURES
                                    CORPORATION, a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    GULFSTAR ENERGY, INC.
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

                                    RANGE ENERGY FINANCE CORPORATION
                                    a Delaware corporation

                                    By:_________________________________________
                                    Name:_______________________________________
                                    Title:______________________________________

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