                                Combat Arms
                              2869 Grove Way
                   Castro Valley, California 94546-6709
                         Telephone (415) 538-6544
                            BBS: (415) 537-1777
                              August 18, 1991


                 SMITH & WESSON METALLURGY VERSUS RUGER'S


          The following message was extracted from the Firearms Echo
     and is a discussion by Ed Harris on the Smith & Wesson pistol
     metal and how, in his view, it compares to that of the Ruger. Ed
     is a former Ruger engineer. You may ask questions of Ed Harris by
     entering a message to him in the Firearms Echo (download
     ECHO_USE.ZIP first for details on how to use the Echoes if you
     are unfamiliar with them; it is a simple process). Ed usually
     responds within a couple of days.


     Richard Bash
     -Your SysOp-

                               -=-=-=-=-=-=-


      -= THE QUESTION THAT WAS ORIGINALLY ASKED BY NEIL HARRINGTON =-


               What are your thoughts on heavy loads in the
               L-frame S&W revolvers? I assume the L frame
               came into existence in an attempt to correct
               shortcomings of the K frame in this caliber.
               Do you think it's successful in this?


                          -= ED HARRIS' REPLY =-


          From my experience testing the L-frame when I was at Ruger,
     it is not. I have no reason to believe the materials or
     production methods have changed since 1984 when I tested them and
     the physical limitations of the design, materials and method of
     manufacture simply preclude the durability which can be obtained
     from the materials Ruger is able to use.

          S&W L-frames only test about Rc20-24 (note Rc = Rockwell C
     scale hardness testing value), which is an improvement over S&W K
     frames (which are often so soft they won't register on the C
     scale at all!). This compared to an Rc35 minimum value on the
     Ruger.

          S&W barrels are re-sulphurized 4140 on the magnums versus
     1137 on the .38 Specials, which are also soft (only about Rc24).
     The Rugers are a vacuum melted low sulphur 4140, which is very
     clean, and typically Rc38-40.

          The S&W lockwork parts are plain carbon steel like a 1035 or
     1040, surface case-hardened. The hammer spur will snap off an S&W
     if the weapon is dropped. You will actually bend the hammer and
     trigger, and/or the yoke and center pin, in a drop test,
     rendering the gun inoperable. I have seen this happen when police
     officers ran up or down stairs and their belly jostled the gun
     out of a holster; the revolver fell onto the stairs and this
     locked up the gun. Ruger's lockwork is usually Rc46 (minimum) all
     the way through and is a low-sulphur 300 series stainless, which
     is very tough and ductile. You cannot break it by securing the
     parts in a vise and striking them with a hammer. The guns will
     still work after repeated drops from 8 feet onto concrete.

          The steel used in S&W cylinders we examined under
     metallography occasionally showed sulphide stringers which can
     limit ultimate strength because they act as stress risers. This
     would worry me as a purchasing agent because I know they only
     fire one proof cartridge per gun; you don't know if a flaw was on
     the other side of the bar, if you have secondary piping or a bad
     crop of the billet at the mill. For this reason, the proofing may
     not be adequate to identify all faulty cylinders. S&W has had
     this problem before when a bar of un-heat treated steel got run
     through production and pieces got out the door because they
     weren't properly proofed. They had no idea anything was wrong
     until blownup guns started coming back from the field.

          Ruger cylinders are proofed with one load per chamber. The
     steel used is also vacuum melted, argon-oxygen decarburized,
     ladle refined and 100% ultrasonic and x-ray inspected nuclear
     grade material with .006% maximum sulphur content. Its structure
     and chemistry are verified to agree with the mill certification
     before a load is released to production. This material is much
     cleaner and stronger, although more difficult to machine.
     Machining it requires the use of carbide tooling and synthetic
     coolants mixed with distilled water and forced through heat
     exchangers, while at the same time on-line process controls
     monitor coolant flow, temperature and cutting tool temperature.

          I was at Ruger during the development of the GP100. The
     design objective was to build a service revolver which would meet
     the U.S. Customs specifications, which required 10,000 rounds
     endurance with full-house .357 Magnum loads with no malfunctions
     and no parts replacements. After the completion of the testing,
     the gun still must pass gaging acceptance for headspace, cylinder
     end play, barrel gap, forcing cone erosion, firing pin energy,
     timing, trigger pull, accuracy and targeting requirements.

          A separate sample was subjected to adverse conditions and
     environmental testing, which included sand, mud, dust, salt
     spray, chemical compatibility of non-metallic parts and safety
     drop testing. Federal contracts were usually subjected to the
     same requirements.

          Competing products were bought from normal trade channels
     through established police equipment distributors and tested
     similarly. These included K frame and L frame revolvers and none
     survived the 10,000 round test or adverse conditions. The only
     ones which did were the Colt Python, the S&W Model 28 and the
     GP100. The old Security Six out performed the S&W K and L frames,
     but did not match the S&W 28, Colt Python or GP100.



     Regards,


     Ed

                         -= END OF MESSAGE =-


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