Exhibit 2.4










                                SECOND AMENDMENT

                                       TO

                            STOCK PURCHASE AGREEMENT

                                     BETWEEN

                            ALLIANT TECHSYSTEMS INC.

                                       AND

                     ATK COMMERCIAL AMMUNITION COMPANY INC.

                                       AND

                             MEADE INSTRUMENTS CORP.

                                       AND

                               MTSC HOLDINGS, INC.





                                      DATED

                                OCTOBER 24, 2002



                               SECOND AMENDMENT TO
                            STOCK PURCHASE AGREEMENT


         This SECOND AMENDMENT TO STOCK PURCHASE AGREEMENT (this "SECOND
AMENDMENT"), dated as of October 14, 2002, is made and entered into by and
between Alliant Techsystems Inc., a Delaware corporation ("SELLER PARENT"), and
ATK Commercial Ammunition Company Inc., a Delaware corporation and an indirect
wholly owned subsidiary of Seller Parent ("SELLER"), on the one hand, and Meade
Instruments Corp., a Delaware corporation ("BUYER PARENT"), and MTSC Holdings,
Inc., a California corporation and a wholly owned subsidiary of Buyer Parent
("BUYER"), on the other.

         WHEREAS, the parties hereto have entered into that certain Stock
Purchase Agreement, dated as of September 14, 2002 (the "Agreement");

         WHEREAS, the parties hereto have entered into that certain First
Amendment to Stock Purchase Agreement, dated as of October 4, 2002 (the "First
Amendment");

         WHEREAS, any capitalized terms used herein and references to sections
and schedules not otherwise defined shall have the meaning ascribed to them in
the Agreement;

         WHEREAS, the parties to the Agreement have agreed to enter into this
Second Amendment to the Agreement;

         NOW, THEREFORE, in consideration of the mutual covenants,
representations, warranties and agreements and the conditions set forth in this
Amendment, the parties agree as follows:


1.1      The parties hereto agree that Section 2.2 of the Agreement is amended
         and restated to read as follows, "As consideration for the Buyer's
         purchase of the Business Shares, on the Closing Date, Buyer shall pay
         to Seller the sum of $16,000,000.00 (the "PURCHASE PRICE"), by wire
         transfer in immediately available funds to an account designated by
         Seller. The Purchase Price shall be adjusted in accordance with Section
         2.3 of this Agreement."

1.2      The other terms and conditions of the Agreement remain unamended and in
         full force and effect as set forth in the Agreement, as revised by the
         First Amendment and this Second Amendment.

                                       1


IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment to be
executed as of the date first above written.


                               ATK COMMERCIAL AMMUNITION
                               COMPANY INC.

                               By:               /S/ Perri A. Hite
                                     ------------------------------------------
                               Name:             Perri A. Hite
                                     ------------------------------------------
                               Title:   Vice President and Secretary
                                     ------------------------------------------


                               ALLIANT TECHSYSTEMS INC.

                               By:               /S/ Michael B. Dolby
                                     ------------------------------------------
                               Name:             Michael B. Dolby
                                     ------------------------------------------
                               Title:   Vice President Corporate
                                     ------------------------------------------
                                        Strategic Development
                                     ------------------------------------------



                               MTSC HOLDINGS, INC.

                               By:               /S/ John C. Diebel
                                     ------------------------------------------
                               Name:             John C. Diebel
                                     ------------------------------------------
                               Title:   Chairman and Chief Executive Officer
                                     ------------------------------------------


                               MEADE INSTRUMENTS CORP.

                               By:               /S/ John C. Diebel
                                     ------------------------------------------
                               Name:             John C. Diebel
                                     ------------------------------------------
                               Title:   Chairman and Chief Executive Officer
                                     ------------------------------------------



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