{"product_id":"smith-wesson-model-51-j-frame-hammer-block-22-magnum-51120","title":"Smith \u0026 Wesson Model 51 J Frame Hammer Block .22 Magnum, Part# 51120","description":"\u003ch2\u003eSmith \u0026amp; Wesson Model 51 Hammer Block – Part# 51120\u003c\/h2\u003e\u003cp\u003eThis is a genuine factory Smith \u0026amp; Wesson hammer block for the J Frame Model 51 revolver chambered in .22 Magnum Rimfire (.22 WMR). An old-style used part in serviceable condition. The hammer block is a critical passive safety component — it prevents the hammer from contacting the firing pin unless the trigger is fully depressed, protecting against accidental discharge from drops or impacts.\u003c\/p\u003e\u003cp\u003eIf your revolver has a worn, cracked, or missing hammer block, replace it immediately before returning the firearm to service.\u003c\/p\u003e\u003ch3\u003ePart Details\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 51120\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Name:\u003c\/strong\u003e Hammer Block\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCondition:\u003c\/strong\u003e Used, factory original (old style)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFrame:\u003c\/strong\u003e J Frame\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCaliber:\u003c\/strong\u003e .22 Magnum Rimfire (.22 WMR \/ .22 M.R.F.)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFunction:\u003c\/strong\u003e Passive drop safety — blocks hammer-to-firing-pin contact unless trigger is fully pulled\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eModel Compatibility\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eCaliber\u003c\/th\u003e\n\u003cth\u003eFrame\u003c\/th\u003e\n\u003cth\u003eCompatible\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel 51\u003c\/td\u003e\n\u003ctd\u003e.22 Magnum (.22 WMR)\u003c\/td\u003e\n\u003ctd\u003eJ Frame\u003c\/td\u003e\n\u003ctd\u003e✅ Yes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel 53\u003c\/td\u003e\n\u003ctd\u003e.22 Jet \/ .22 LR\u003c\/td\u003e\n\u003ctd\u003eJ Frame\u003c\/td\u003e\n\u003ctd\u003e⚠️ Verify fitment\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel 63\u003c\/td\u003e\n\u003ctd\u003e.22 LR (rimfire)\u003c\/td\u003e\n\u003ctd\u003eJ Frame\u003c\/td\u003e\n\u003ctd\u003e⚠️ Verify fitment — different rimfire caliber\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel 34\u003c\/td\u003e\n\u003ctd\u003e.22 LR (rimfire)\u003c\/td\u003e\n\u003ctd\u003eJ Frame\u003c\/td\u003e\n\u003ctd\u003e⚠️ Verify fitment — different rimfire caliber\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel 36 \/ 60\u003c\/td\u003e\n\u003ctd\u003e.38 Special \/ .357 Mag\u003c\/td\u003e\n\u003ctd\u003eJ Frame\u003c\/td\u003e\n\u003ctd\u003e⚠️ Verify fitment — centerfire\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eK \/ L \/ N Frame\u003c\/td\u003e\n\u003ctd\u003eVarious\u003c\/td\u003e\n\u003ctd\u003eLarger frames\u003c\/td\u003e\n\u003ctd\u003e❌ Different frame size\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003e\u003cem\u003eNote: The Model 51 is chambered in .22 Magnum Rimfire (.22 WMR) — not .22 LR. Hammer blocks are frame-specific and not interchangeable between J, K, L, or N Frame revolvers. Parts may also vary between rimfire caliber configurations (.22 WMR vs .22 LR) and between old-style and current-production revolvers. Always confirm your exact model before ordering. Model numbers are stamped on the frame behind the yoke when the cylinder is swung out.\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eInstallation\u003c\/h3\u003e\u003cp\u003eHammer block replacement requires full disassembly of the lock work. As a critical safety component, we strongly recommend installation by a qualified gunsmith. Do not return the firearm to service without verifying correct function after installation.\u003c\/p\u003e\u003cp\u003eQuestions about fitment? Call or email us — we're happy to help.\u003c\/p\u003e","brand":"Smith \u0026 Wesson","offers":[{"title":"Default Title","offer_id":40821871542330,"sku":"51120","price":6.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1423\/2020\/files\/DSC06708.jpg?v=1741966622","url":"https:\/\/usagunsandgear.com\/products\/smith-wesson-model-51-j-frame-hammer-block-22-magnum-51120","provider":"USA Guns And Gear","version":"1.0","type":"link"}