<PAGE>   1
                                                                   Exhibit 10.31

                       THIRD AMENDMENT TO CREDIT AGREEMENT


                  This Amendment is made as of the 1st day of May, 1998 by and
between ROYAL GRIP, INC., a Nevada corporation ("Royal Grip") and ROXXI, INC., a
Nevada corporation ("Roxxi") (collectively, the "Borrower"), and NORWEST
BUSINESS CREDIT, INC., a Minnesota corporation (the "Lender").

                                    Recitals

                  The Borrower and the Lender have entered into the Credit and
Security Agreement dated as of February 10, 1997, as amended by that certain
First Amendment to Credit Agreement dated April 11, 1997, as amended by that
certain Second Amendment to Credit Agreement dated August 28, 1997
(collectively, the "Credit Agreement").

                  The Lender has agreed to make certain loan advances to the
Borrower pursuant to the terms and conditions set forth in the Credit Agreement.

                  The loan advances under the Credit Agreement are evidenced by
the Borrower's Revolving and Term Note dated as of February 10, 1997, in the
maximum principal amount of $2,450,000.00 and payable to the order of the Lender
(the "Note").

                  All indebtedness of the Borrower to the Lender is secured
pursuant to the terms of the Credit Agreement and all other Security Documents
as defined therein (collectively, the "Security Documents").

                  The Borrower has requested that certain amendments be made to
the Credit Agreement, which the Lender is willing to make pursuant to the terms
and conditions set forth herein.

                  NOW, THEREFORE, in consideration of the premises and of the
mutual covenants and agreements herein contained, it is agreed as follows:

     1. Terms used in this Amendment which are defined in the Credit Agreement
shall have the same meanings as defined therein, unless otherwise defined
herein.

     2. Prior to the date of this Amendment, the Borrower has (i) failed to
submit audited fiscal year end financial statements within 90 days of the fiscal
year ending 1997 as required by Section 6.1(a) of the Credit Agreement, (ii)
allowed Bob Burg to resign as President of Royal Grip and allowed Danny Edwards
to resign as Chief Executive Officer of Royal Grip in violation of Section 7.20
of the Credit Agreement, (iii) made advances to Royal Precision, FM Precision
Golf Corp., and FMPSUB, Inc., in excess of $25,000.00 in violation of Section
7.4(iv) of the Credit Agreement, and (iv) changed Royal Grip's fiscal year end
from December 31 to May 31 in violation of Section 7.11 of the Credit Agreement
(collectively the "Current Defaults"). Upon satisfaction by Borrower of all of
the terms and conditions set forth in this Amendment, the Lender, although under
no obligation to do so, shall waive the Current Defaults. 

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<PAGE>   2

Nothing herein shall be construed as a waiver by Lender of any existing default
or Default Period under the terms of the Credit Agreement other than the Current
Defaults. Nothing herein shall be construed as obligating Lender to waive any
future defaults or Default Period under the Credit Agreement including any
future defaults or Default Period under Sections 6.1, 7.4, 7.11 and 7.20 of the
Credit Agreement. Upon the satisfaction of all of the terms and conditions set
forth in this Amendment, the Default Period arising as a result of the Current
Defaults shall be deemed to have ceased.

                  3. The Credit Agreement is hereby amended as follows:

                           (a) Section 6.1(a) of the Credit Agreement is hereby
deleted in its entirety and replaced as follows:

                                    (a) as soon as available, and in any event
                  within 90 days after the end of each fiscal year of the
                  Borrower, (i) unaudited consolidating financial statements,
                  prepared by the accountants described below, of FM Precision
                  Golf Corp., Royal Grip and Roxxi, which financial statements
                  shall include the balance sheets of said entities as of the
                  end of such fiscal year and the related statements of income,
                  retained earnings and cash flows of said entities for the
                  fiscal year then ended, all in reasonable detail and prepared
                  in accordance with generally accepted accounting principles
                  applied on a consistent basis with the accounting practices
                  applied in the financial statements referred to in Section
                  5.5, and (ii) consolidated audited financial statements of
                  Royal Precision, Inc. with the unqualified opinion of Arthur
                  Andersen, L.L.P. or such other independent certified public
                  accountants selected by the Borrower and acceptable to the
                  Lender, which annual financial statements shall include the
                  consolidated balance sheet of FM Precision Golf Corp., Royal
                  Grip and Roxxi as at the end of such fiscal year and the
                  related consolidated statements of income, retained earnings
                  and cash flows, all in reasonable detail and prepared in
                  accordance with generally accepted accounting principles
                  applied on a basis consistent with the accounting practices
                  applied in the financial statements referred to in Section 5.5
                  hereof, together with (1) a report signed by such accountants
                  stating that in making the investigations necessary for said
                  opinion they obtained no knowledge, except as specifically
                  stated, of any Default or Event of Default hereunder and all
                  relevant facts in reasonable detail to evidence, and the
                  computations as to, whether or not the Borrower is in
                  compliance with the requirements set forth in Sections 6.12
                  through 6.14 and Section 7.10 hereof; and (2) a certificate of
                  the Vice President of Finance or any other officer of each of
                  Royal Grip and Roxxi stating that FM Precision Golf Corp.'s,
                  Roxxi's and Royal Grip's unaudited consolidating financial
                  statements have been prepared in accordance with generally
                  accepted accounting 

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<PAGE>   3

                  principles applied on a basis consistent with the accounting
                  practices reflected in the annual financial statements
                  referred to in Section 5.5 hereof and whether or not such
                  officer has knowledge of the occurrence of any Default or
                  Event of Default hereunder and, if so, stating in reasonable
                  detail the facts with respect thereto;

                           (b) Section 6.12 of the Credit Agreement is hereby
deleted in its entirety and replaced as follows:

                           Section 6.12 DEBT SERVICE COVERAGE RATIO. The
                  Borrower agrees that it shall, as of the last day of each
                  fiscal year, commencing on May 31, 1998 (based upon the
                  immediately preceding five month period) and continuing each
                  fiscal year thereafter (based upon the immediately preceding
                  twelve month period), maintain a minimum debt service coverage
                  ratio of 1.0 to 1.

                           The debt service coverage ratio shall be calculated
                  according to the following formula:


<TABLE>
<S>               <C>
                  FUNDS FROM OPERATIONS + INTEREST EXPENSE - UNFINANCED PORTION OF CAPITAL EXPENDITURES 
                  -------------------------------------------------------------------------------------
                  Current Maturities Long-Term Debt (actually paid during the period) + Interest Expense
</TABLE>

                  (c) Section 6.13 of the Credit Agreement is hereby deleted in
its entirety and replaced as follows:

                           Section 6.13 NET WORTH. The Borrower warrants that,
                  as of December 31, 1997 Borrower had a minimum Net Worth of
                  not less than $3,700,000.00.

                           The Borrower covenants that its minimum Net Worth as
                  of the end of each month listed below shall increase by not
                  less than (or in the event a decrease is allowed, decrease by
                  not more than) the amounts set forth below as measured from
                  the Borrower's Net Worth as of the applicable measurement date
                  set forth below.
<TABLE>
<CAPTION>

                    MONTH ENDING               CUMULATIVE NET          MEASUREMENT DATE
                                               WORTH INCREASE 
                                                 (DECREASE)
<S>                                                <C>                 <C>
                    March 31, 1998                 ($85,000.00)        December 31, 1997
                    April 30, 1998                 ($85,000.00)        December 31, 1997
                    May 31, 1998                   ($85,000.00)        December 31, 1997
                    June 30, 1998                   $12,000.00         May 31, 1998
                    July 31, 1998                   $24,000.00         May 31, 1998
                    August 31, 1998                 $39,000.00         May 31, 1998
                    September 30, 1998              $57,000.00         May 31, 1998
                    October 31, 1998                $39,000.00         May 31, 1998
</TABLE>

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<PAGE>   4
<TABLE>
<CAPTION>

<S>                                                <C>                 <C>
                    November 30, 1998               $39,000.00         May 31, 1998
                    December 31, 1998                  $0.00           May 31, 1998
                    January 31, 1999 and           ($45,000.00)        May 31, 1998 and for each
                    each January thereafter                            January thereafter the
                                                                       immediately preceding May
                                                                       31
                    February 28, 1999 and          ($50,000.00)        May 31, 1998 and for each
                    each February thereafter                           February thereafter the
                                                                       immediately preceding May
                                                                       31
                    March 31, 1999 and each        ($15,000.00)        May 31, 1998 and for each
                    March thereafter                                   March thereafter the
                                                                       immediately preceding May
                                                                       31
                    April 30, 1999 and each         $20,000.00         May 31, 1998 and for each
                    April thereafter                                   April thereafter the
                                                                       immediately preceding May
                                                                       31
                    May 31, 1999 and each           $48,000.00         May 31, 1998 and for each
                    May thereafter                                     May thereafter the
                                                                       immediately preceding May
                                                                       31
                    June 30, 1999 and each          $12,000.00         May 31, 1999 and for each
                    June thereafter                                    June thereafter the
                                                                       immediately preceding May
                                                                       31
                    July 31, 1999 and each          $24,000.00         May 31, 1999 and for each
                    July thereafter                                    July thereafter the
                                                                       immediately preceding May
                                                                       31
                    August 31, 1999 and             $39,000.00         May 31, 1999 and for each
                    each August thereafter                             August thereafter the
                                                                       immediately preceding May
                                                                       31
                    September 30, 1999 and          $57,000.00         May 31, 1999 and for each
                    each September                                     September thereafter the
                    thereafter                                         immediately preceding May
                                                                       31
                    October 31, 1999 and            $39,000.00         May 31, 1999 and for each
                    each October thereafter                            October thereafter the
                                                                       immediately preceding May
                                                                       31
                    November 30, 1999 and           $39,000.00         May 31, 1999 and for each
                    each November thereafter                           November thereafter the
                                                                       immediately preceding May
                                                                       31
                    December 31, 1999 and              $0.00           May 31, 1999 and for each
                    each December thereafter                           December thereafter the
                                                                       immediately preceding May
                                                                       31
</TABLE>

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<PAGE>   5

                           (d) Section 6.14 of the Credit Agreement is hereby
deleted in its entirety and replaced as follows:

                           6.14 NET INCOME. The Borrower covenants that it shall
                  achieve a Net Income of not less than (or in the event a Net
                  Loss is allowed, achieve a Net Loss of not more than) the
                  amounts set forth below as measured from the applicable
                  Measurement Date set forth below:
<TABLE>
<CAPTION>

                    MONTH ENDING                NET INCOME/NET         MEASUREMENT DATE
                                                       LOSS
<S>                                                <C>                 <C>
                    March 31, 1998                 ($85,000.00)        December 31, 1997
                    April 30, 1998                 ($85,000.00)        December 31, 1997
                    May 31, 1998                   ($85,000.00)        December 31, 1997
                    June 30, 1998                   $12,000.00         May 31, 1998
                    July 31, 1998                   $24,000.00         May 31, 1998
                    August 31, 1998                 $39,000.00         May 31, 1998
                    September 30, 1998              $57,000.00         May 31, 1998
                    October 31, 1998                $39,000.00         May 31, 1998
                    November 30, 1998               $39,000.00         May 31, 1998
                    December 31, 1998                  $0.00           May 31, 1998
                    January 31, 1999 and           ($45,000.00)        May 31, 1998 and for each
                    each January thereafter                            January thereafter the
                                                                       immediately preceding May
                                                                       31
                    February 28, 1999 and          ($50,000.00)        May 31, 1998 and for each
                    each February thereafter                           February thereafter the
                                                                       immediately preceding May
                                                                       31
                    March 31, 1999 and each        ($15,000.00)        May 31, 1998 and for each
                    March thereafter                                   March thereafter the
                                                                       immediately preceding May
                                                                       31
                    April 30, 1999 and each         $20,000.00         May 31, 1998 and for each
                    April thereafter                                   April thereafter the
                                                                       immediately preceding May
                                                                       31
                    May 31, 1999 and each           $48,000.00         May 31, 1998 and for each
                    May thereafter                                     May thereafter the
                                                                       immediately preceding May
                                                                       31
                    June 30, 1999 and each          $12,000.00         May 31, 1999 and for each
                    June thereafter                                    June thereafter the
                                                                       immediately preceding May
                                                                       31
                    July 31, 1999 and each          $24,000.00         May 31, 1999 and for each
                    July thereafter                                    July thereafter the
                                                                       immediately preceding May
                                                                       31
                    August 31, 1999 and             $39,000.00         May 31, 1999 and for each
                    each August thereafter                             August thereafter the
                                                                       immediately preceding May
                                                                       31
</TABLE>

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<TABLE>
<CAPTION>
<S>                                                 <C>                <C>
                    September 30, 1999 and          $57,000.00         May 31, 1999 and for each
                    each September                                     September thereafter the
                    thereafter                                         immediately preceding May
                                                                       31
                    October 31, 1999 and            $39,000.00         May 31, 1999 and for each
                    each October thereafter                            October thereafter the
                                                                       immediately preceding May
                                                                       31
                    November 30, 1999 and           $39,000.00         May 31, 1999 and for each
                    each November thereafter                           November thereafter the
                                                                       immediately preceding May
                                                                       31
                    December 31, 1999 and              $0.00           May 31, 1999 and for each
                    each December thereafter                           December thereafter the
                                                                       immediately preceding May
                                                                       31
</TABLE>

                           Notwithstanding anything to the contrary, beginning
                  with March of 1998, and continuing for each month thereafter,
                  the Borrower shall not suffer a Net Loss in excess of (i)
                  $100,000.00 in any month of February, March, April, May, June,
                  July, August, September, October or November, or (ii)
                  $130,000.00 in any month of December or January

                           (e) The figure "$25,000.00" contained in Section
7.14(iv) is hereby deleted and replaced with the figure "$100,000.00".

                           (f) Section 7.10 of the Credit Agreement is hereby
deleted in its entirety and replaced as follows:

                           7.10 CAPITAL EXPENDITURES. The Borrower will not
                  expend or contract to make unfinanced Capital Expenditure
                  greater than $450,000.00 in the aggregate during any fiscal
                  year for the lease, purchase or other acquisition of any
                  capital asset, or for the lease of any other asset, whether
                  payable currently or in the future.

                  4. Except as specifically amended by this Amendment, all of
the terms and conditions of the Credit Agreement shall remain in full force and
effect and shall apply to any Advance thereunder.

                  5. This Amendment shall be effective upon receipt by the
Lender of an executed original hereof, together with each of the following, each
in substance and form acceptable to the Lender in its sole discretion:

                           (a) Certificate of the Secretary of the Borrower
certifying as to (i) the resolutions of the board of directors of the Borrower
approving the execution and delivery of this 

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<PAGE>   7

Amendment, (ii) the fact that the Articles of Incorporation and Bylaws of the
Borrower, which were certified and delivered to the Lender in connection with
the execution and delivery of the Credit Agreement continue in full force and
effect and have not been amended or otherwise modified except as set forth in
the Certificate to be delivered, and (iii) certifying that the officers and
agents of the Borrower who have been certified to the Lender as being authorized
to sign and to act on behalf of the Borrower continue to be so authorized.

         6. The Borrower hereby represents and warrants to the Lender as
follows:

                  (a) The Borrower has all requisite power and authority to
execute this Amendment and to perform all of its obligations hereunder, and this
Amendment has been duly executed and delivered by the Borrower and constitutes
the legal, valid and binding obligation of the Borrower, enforceable in
accordance with its terms.

                  (b) The execution, delivery and performance by the Borrower of
this Amendment have been duly authorized by all necessary corporate action and
do not (i) require any authorization, consent or approval by any governmental
department, commission, board, bureau, agency or instrumentality, domestic or
foreign, (ii) violate any provision of any law, rule or regulation or of any
order, writ, injunction or decree presently in effect, having applicability to
the Borrower, or the articles of incorporation or by-laws of the Borrower, or
(iii) result in a breach of or constitute a default under any indenture or loan
or credit agreement or any other agreement, lease or instrument to which the
Borrower is a party or by which it or its properties may be bound or affected.

                  (c) All of the representations and warranties contained in
Article V of the Credit Agreement are correct on and as of the date hereof as
though made on and as of such date, except to the extent that such
representations and warranties relate solely to an earlier date.

         7. All references in the Credit Agreement to "this Agreement" shall be
deemed to refer to the Credit Agreement as amended hereby; and any and all
references in the Security Documents to the Credit Agreement shall be deemed to
refer to the Credit Agreement as amended hereby.

         8. From the date of this Amendment forward, Exhibit D of the Credit
Agreement shall be amended to comply with the revisions to the Credit Agreement
contained herein.

         9. Except as specifically set forth in Section 2 above, the execution
of this Amendment and acceptance of any documents related hereto shall not be
deemed to be a waiver of any Default, Event of Default or Default Period under
the Credit Agreement or breach, default or event of default under any Security
Document or other document held by the Lender, whether or not known to the
Lender and whether or not existing on the date of this Amendment.

         10. The Borrower hereby absolutely and unconditionally releases and
forever discharges the Lender, and any and all participants, parent
corporations, subsidiary corporations, affiliated corporations, insurers,
indemnitors, successors and assigns thereof, together with all of 


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<PAGE>   8

the present and former directors, officers, agents and employees of any of the
foregoing, from any and all claims, demands or causes of action of any kind,
nature or description, whether arising in law or equity or upon contract or tort
or under any state or federal law or otherwise, which the Borrower has had, now
has or has made claim to have against any such person for or by reason of any
act, omission, matter, cause or thing whatsoever arising from the beginning of
time to and including the date of this Amendment, whether such claims, demands
and causes of action are matured or unmatured or known or unknown.

         11. The Borrower hereby reaffirms its agreement under the Credit
Agreement to pay or reimburse the Lender on demand for all costs and expenses
incurred by the Lender in connection with the Credit Agreement, the Security
Documents and all other documents contemplated thereby, including without
limitation all reasonable fees and disbursements of legal counsel. Without
limiting the generality of the foregoing, the Borrower specifically agrees to
pay all fees and disbursements of counsel to the Lender for the services
performed by such counsel in connection with the preparation of this Amendment
and the documents and instruments incidental hereto. The Borrower hereby agrees
that the Lender may, at any time or from time to time in its sole discretion and
without further authorization by the Borrower, make a loan to the Borrower under
the Credit Agreement, or apply the proceeds of any loan, for the purpose of
paying any such fees, disbursements, costs and expenses.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the day and year first above written.

                                          ROYAL GRIP, INC., a Nevada corporation


                                          By /s/ Thomas Schneider
                                            ------------------------------------

                                            Its  Treasurer
                                               ---------------------------------


                                          ROXXI, INC., a Nevada corporation


                                          By /s/ Thomas Schneider
                                            ------------------------------------

                                            Its  Treasurer
                                               ---------------------------------

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<PAGE>   9

                                          NORWEST BUSINESS CREDIT, INC., a 
                                            Minnesota corporation


                                          By /s/ [ILLEGIBLE SIGNATURE]
                                            ------------------------------------

                                            Its  Vice President
                                               ---------------------------------

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