{"product_id":"smith-wesson-model-19-4-strain-screw-round-butt-19172","title":"S\u0026W K Frame Model 19-4 Strain Screw, Old Style, Round Butt - Part# 19172","description":"\u003ch2\u003eSmith \u0026amp; Wesson K Frame Model 19-4 Strain Screw - Part 19172\u003c\/h2\u003e\n\u003cp\u003eAuthentic Smith \u0026amp; Wesson old-style strain screw for K Frame Model 19-4 Combat Magnum revolvers with round butt grip frames. This vintage OEM factory part controls mainspring tension, directly affecting trigger pull weight and hammer function for reliable performance.\u003c\/p\u003e\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVintage OEM Part:\u003c\/strong\u003e Genuine Smith \u0026amp; Wesson factory component manufactured to exact specifications\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOld-Style Design:\u003c\/strong\u003e Period-correct strain screw for classic Model 19-4 revolvers\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMainspring Tension Control:\u003c\/strong\u003e Regulates hammer spring pressure for consistent trigger pull and reliable ignition\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRound Butt Configuration:\u003c\/strong\u003e Specifically designed for round butt grip frames\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUsed Condition:\u003c\/strong\u003e Functional vintage part showing normal wear consistent with previous use\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eCompatible Models\u003c\/h3\u003e\n\u003cp\u003eThis strain screw is designed specifically for Smith \u0026amp; Wesson K Frame revolvers with round butt grip frames:\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eK Frame Models (Round Butt, Old Style):\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eModel 19 Combat Magnum - .357 Magnum (round butt variants)\u003c\/li\u003e\n\u003cli\u003eModel 19-2, 19-3, 19-4 - .357 Magnum (round butt variants)\u003c\/li\u003e\n\u003cli\u003eModel 66 Combat Magnum - .357 Magnum (round butt variants)\u003c\/li\u003e\n\u003cli\u003eModel 13, 65, 67 - .357 Magnum \/ .38 Special (round butt variants)\u003c\/li\u003e\n\u003cli\u003eOther vintage K Frame models with round butt configuration requiring old-style strain screws\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eHistorical Context:\u003c\/strong\u003e The Model 19 Combat Magnum was introduced in 1955 at the request of legendary lawman Bill Jordan. Built on the medium K Frame, it offered .357 Magnum power in a lighter, more compact package than the N Frame Model 27.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e This is an old-style strain screw for round butt models only. Not compatible with square butt models or newer production runs using updated strain screw designs. Verify your revolver's grip frame configuration and production era before ordering.\u003c\/p\u003e\n\u003ch3\u003eInstallation\u003c\/h3\u003e\n\u003cp\u003eProfessional gunsmith installation strongly recommended. Disassembly and reassembly of the revolver's internal action required. Some fitting may be necessary by a qualified gunsmith to ensure proper mainspring tension and trigger function.\u003c\/p\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 19172\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Smith \u0026amp; Wesson\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCondition:\u003c\/strong\u003e Used\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFrame Type:\u003c\/strong\u003e K Frame\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGrip Frame Type:\u003c\/strong\u003e Round Butt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStyle:\u003c\/strong\u003e Old Style (Vintage)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Caliber:\u003c\/strong\u003e .357 Magnum\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 1 oz\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003ePreserve the authenticity of your vintage Smith \u0026amp; Wesson K Frame revolver with genuine OEM parts.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQuestions?\u003c\/strong\u003e Contact us at sales@usagunsandgear.com or call 770-544-8075 for technical support and compatibility verification.\u003c\/p\u003e","brand":"Smith \u0026 Wesson","offers":[{"title":"Default Title","offer_id":31984161390650,"sku":"19172","price":6.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1423\/2020\/products\/DSC00433.jpg?v=1779983835","url":"https:\/\/usagunsandgear.com\/products\/smith-wesson-model-19-4-strain-screw-round-butt-19172","provider":"USA Guns And Gear","version":"1.0","type":"link"}