{
  "apiVersion": 1,
  "kind": "work-order",
  "purpose": "Taking the firearm apart for a job such as refinishing, and putting it back together to specification.",
  "firearm": {
    "slug": "hk-mark-23",
    "name": "Heckler & Koch Mark 23",
    "manufacturer": {
      "id": "heckler-koch",
      "name": "Heckler & Koch"
    },
    "category": "pistol",
    "action": "hammer-fired-short-recoil",
    "calibers": [
      ".45 ACP"
    ],
    "alsoKnownAs": [
      "Mk 23 Mod 0",
      "USSOCOM Offensive Handgun"
    ],
    "coversAlso": [
      "H&K Mk 23 Mod 0",
      "H&K SOCOM pistol"
    ],
    "page": "firearms/hk-mark-23.html",
    "bundle": "api/v1/firearms/hk-mark-23.json",
    "lastUpdated": "2026-10-29"
  },
  "notices": [
    "This work order is written for the Heckler & Koch Mark 23. It is reported to cover H&K Mk 23 Mod 0; H&K SOCOM pistol — if the firearm on the bench is one of those, check the torque notes: values do not always carry over.",
    "No torque values are recorded for this firearm. Get them from the manufacturer or a gunsmith; do not estimate."
  ],
  "disclaimer": {
    "headline": "Read this before you use anything here.",
    "points": [
      "This is a guide, not an authority. Entries are compiled from manufacturer manuals, technical manuals, published references, and community knowledge. Some of it comes from sources that are not authoritative, and some of it may simply be wrong.",
      "Always consult the manufacturer's manual for your specific firearm and serial-number range. Manufacturers change designs mid-production without renaming the model. The manual that shipped with your firearm outranks anything on this site.",
      "Consult a licensed gunsmith for anything beyond routine field stripping and cleaning, for any firearm you are unsure about, and for any procedure marked as gunsmith-recommended here.",
      "Treat every firearm as loaded. Verify it is unloaded, with the magazine removed and the chamber physically and visually checked, before any procedure in this database. Point it in a safe direction the entire time.",
      "Disassembly can damage a firearm or injure you. Springs are under tension, parts can launch, and reassembling a firearm incorrectly can make it unsafe to fire in a way that is not obvious from the outside. If a reassembled firearm does not pass a function check, stop and see a gunsmith.",
      "Torque values are shown in two groups. Values from the manufacturer or the issuing military are shown as such, with the document they came from. Values reported by anyone else — parts makers, gunsmithing publishers, articles, forums — are shown separately with who said them, how reliable that source is, and their exact words. Those are not specifications. Confirm any torque value with the manufacturer or a licensed gunsmith before relying on it.",
      "Nothing here is legal advice. Firearms law varies by country, state, and city, and some modifications or configurations are regulated or prohibited. You are responsible for knowing and following the law where you are.",
      "No warranty of any kind. Contributors and maintainers accept no liability for damage, injury, or loss arising from use of this material."
    ],
    "page": "disclaimer.html",
    "legal": {
      "summary": "Legal notice: this material is third-party information compiled from sources of varying reliability and is provided for general informational and educational purposes only. It is not gunsmithing, technical, safety or legal advice, it is not verified or endorsed by any manufacturer, and it must not be taken as fact. Any work on a firearm beyond the routine field stripping described in its own owner's manual should be performed only by a licensed and insured gunsmith. You use this material entirely at your own risk. Fundamental Build LLC and the project's contributors make no warranty of any kind and accept no liability for death, injury, damage or loss arising from its use. Full terms: LEGAL.md.",
      "page": "legal.html",
      "notice": "https://github.com/Fundamental-build-LLC/Pew-Takedown/blob/main/LEGAL.md"
    }
  },
  "sourcing": {
    "confidence": "high",
    "verification": "manufacturer-manual-verified"
  },
  "manufacturerDisassembly": {
    "status": "published",
    "limit": null,
    "statement": null,
    "source": {
      "title": "Heckler & Koch Mark 23 Operator’s Manual",
      "publisher": "Heckler & Koch",
      "reliability": "primary",
      "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
      "page": "24",
      "pdfPage": 24,
      "pageUrl": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf#page=24",
      "quote": null
    }
  },
  "recalls": [],
  "shopTier": {
    "tier": 3,
    "group": "pistol",
    "rating": "Pew-Takedown editorial rating (1 easy – 3 hardest), not the manufacturer's",
    "reason": "76 line items in HK's list (65 positions plus variants), past the Tier 3 line; HK marks the decocking lever, decocking spring and ejector roll pin 'contact HK for service', the decocker rides on a C-clip, and the recoil/buffer spring assembly and slide release are known to fight reassembly. Many parts plus factory-only steps.",
    "confidence": "medium",
    "partCount": {
      "value": 69,
      "kind": "line-items",
      "covers": "Mark 23 pistol, single list covering 12-rd and 10-rd magazine parts and sight-height variants; the parts list on this page (exploded diagram p. 47); 76 pieces",
      "basis": "manufacturer-parts-list",
      "source": {
        "title": "Heckler & Koch Mark 23 Operator’s Manual",
        "publisher": "Heckler & Koch",
        "reliability": "primary",
        "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
        "page": "46",
        "pdfPage": 46,
        "pageUrl": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf#page=46",
        "quote": "65 guiding part (molded into frame)"
      }
    },
    "painPoints": [
      {
        "issue": "HK reserves the decocking lever, decocking spring and ejector roll pin for factory service, so a full frame strip runs into parts HK says not to touch.",
        "during": "both",
        "source": {
          "title": "Heckler & Koch Mark 23 Operator’s Manual",
          "publisher": "Heckler & Koch",
          "reliability": "primary",
          "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
          "page": null,
          "pdfPage": null,
          "pageUrl": null,
          "quote": "** contact HK for service"
        }
      },
      {
        "issue": "The decocker and its spring are held on the decocking lever axle by a small C-clip.",
        "during": "both",
        "source": {
          "title": "Heckler & Koch Mark 23 Operator’s Manual",
          "publisher": "Heckler & Koch",
          "reliability": "primary",
          "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
          "page": null,
          "pdfPage": null,
          "pageUrl": null,
          "quote": "c-clip (decocker)"
        }
      },
      {
        "issue": "The barrel's high-temperature O-ring must be inspected or replaced when the barrel goes back in, or accuracy suffers.",
        "during": "reassembly",
        "source": {
          "title": "Heckler & Koch Mark 23 Operator’s Manual",
          "publisher": "Heckler & Koch",
          "reliability": "primary",
          "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
          "page": null,
          "pdfPage": null,
          "pageUrl": null,
          "quote": "Inspect or replace the O-ring."
        }
      }
    ],
    "minutes": {
      "strip": 45,
      "rebuild": 70,
      "basis": "estimated",
      "note": "Estimate for an experienced tech with the right tools, detail strip to coatable parts (slide internals, frame pins, trigger group, sights) and rebuild to a function-checked gun; scale used across pistols: Glock-pattern 15/20 min, other strikers 20-30/25-40, DA/SA hammer guns 30-35/45-50, Hi-Power, Colt 1903 and Mark 23 40-45/60-75.",
      "source": null
    },
    "stripScope": [
      {
        "assembly": "Slide",
        "removes": [
          "firing pin, spring and retaining pin",
          "firing pin block and spring",
          "extractor, pin and spring",
          "rear sight and screw",
          "front sight"
        ]
      },
      {
        "assembly": "Barrel / recoil",
        "removes": [
          "barrel and O-ring",
          "recoil spring, guide rod, buffer spring and retainers (dual roll pin, spring ring, washer)"
        ]
      },
      {
        "assembly": "Frame",
        "removes": [
          "slide release lever and spring",
          "magazine release, spring and pin",
          "safety levers, roll pin, detent and spring",
          "trigger, pin and trigger bar with spring",
          "hammer, axle, strut, springs",
          "sear, spring, actuator, axle, sear block",
          "decocker and C-clip",
          "decocking lockout",
          "locking bolt"
        ],
        "tools": [
          "roll-pin punches",
          "snap-ring pliers"
        ]
      },
      {
        "assembly": "Factory only",
        "removes": [
          "decocking lever, decocking spring, ejector roll pin (contact HK for service)"
        ]
      }
    ],
    "hardware": {
      "pins": 11,
      "springs": 16,
      "detents": 2,
      "basis": "counted from the manufacturer's parts list (one per key number unless a quantity is given)"
    },
    "specialTools": [
      {
        "tool": "Snap-ring / C-clip pliers",
        "usedFor": "Decocker C-clip"
      },
      {
        "tool": "Roll-pin punches",
        "usedFor": "Buffer spring retainer dual roll pin, safety lever roll pin"
      }
    ],
    "fitOnRebuild": [
      {
        "check": "Barrel O-ring condition",
        "why": "The O-ring holds barrel position for accuracy; HK says inspect or replace",
        "source": {
          "title": "Heckler & Koch Mark 23 Operator’s Manual",
          "publisher": "Heckler & Koch",
          "reliability": "primary",
          "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
          "page": null,
          "pdfPage": null,
          "pageUrl": null,
          "quote": "Inspect or replace the O-ring."
        }
      },
      {
        "check": "Recoil/buffer spring assembly seated",
        "why": "A mis-seated buffer assembly will not let the slide go on",
        "source": null
      },
      {
        "check": "Sight position / re-zero",
        "why": "Drift or pressed sights moved for coating shift point of impact unless witness-marked and returned to the same spot",
        "source": null
      },
      {
        "check": "Full function check (trigger reset, safeties, slide lock-back, drop of striker/hammer only on trigger)",
        "why": "Standard after any fire-control strip; confirms springs and sears went back correctly",
        "source": null
      }
    ],
    "assessed": "2026-10-29"
  },
  "videos": [],
  "configurations": [],
  "tools": [],
  "phases": [
    {
      "id": "clear",
      "title": "Clear and make safe",
      "steps": [
        {
          "n": 1,
          "instruction": "Point the muzzle in a safe direction and keep your finger off the trigger."
        },
        {
          "n": 2,
          "instruction": "Press the magazine release and remove the magazine.",
          "partsFreed": [
            "Magazine"
          ]
        },
        {
          "n": 3,
          "instruction": "Retract the slide fully to eject any chambered round and lock it open."
        },
        {
          "n": 4,
          "instruction": "Visually inspect the chamber and magazine well, then physically feel the chamber to confirm it is empty.",
          "warning": "Look and feel. Both, every time."
        },
        {
          "n": 5,
          "instruction": "Remove all live ammunition from the work area."
        }
      ],
      "videos": []
    },
    {
      "id": "disassemble",
      "title": "Disassemble",
      "videos": [],
      "procedures": [
        {
          "procedure": "field-strip",
          "title": "Field Strip",
          "level": "field-strip",
          "configuration": false,
          "steps": [
            {
              "n": 1,
              "instruction": "Complete the clearing and safety procedure."
            },
            {
              "n": 2,
              "instruction": "Remove the thread protector from the barrel by rotating it counter-clockwise.",
              "partsFreed": [
                "Thread protector"
              ]
            },
            {
              "n": 3,
              "instruction": "Depress the slide release and allow the slide to move forward."
            },
            {
              "n": 4,
              "instruction": "Remove any mounted accessories."
            },
            {
              "n": 5,
              "instruction": "Retract and hold the slide to the rear about 22 mm, until the front end of the slide release is centred on the recess visible on the left side of the slide.",
              "tip": "HK gives the distance — roughly 22 mm — but the recess alignment is what actually matters."
            },
            {
              "n": 6,
              "instruction": "Push the slide release into the recess on the right side of the frame, then lift and completely remove the slide release from the left side.",
              "partsFreed": [
                "Slide release"
              ]
            },
            {
              "n": 7,
              "instruction": "Slide the slide, with barrel and captured recoil/buffer spring assembly, forward off the frame.",
              "warning": "Keep control of the recoil assembly as the slide comes off.",
              "partsFreed": [
                "Slide assembly"
              ]
            },
            {
              "n": 8,
              "instruction": "Remove the captured recoil/buffer spring assembly by lifting up on the REAR of the guide rod, then lifting the whole assembly out of the slide.",
              "warning": "The assembly is captured. Do not disassemble it.",
              "partsFreed": [
                "Recoil/buffer spring assembly"
              ]
            },
            {
              "n": 9,
              "instruction": "Lift the rear of the barrel by the locking block and withdraw it from the slide.",
              "partsFreed": [
                "Barrel"
              ]
            },
            {
              "n": 10,
              "instruction": "Inspect the O-ring near the muzzle and replace it if worn.",
              "tip": "This is the part that holds the barrel tight in the slide during firing and is what the Mark 23's accuracy depends on."
            }
          ]
        }
      ]
    },
    {
      "id": "refinish",
      "title": "Refinish",
      "components": [
        {
          "name": "Thread protector",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 2
        },
        {
          "name": "Slide release",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 6
        },
        {
          "name": "Slide assembly",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 7
        },
        {
          "name": "Recoil/buffer spring assembly",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 8
        },
        {
          "name": "Barrel",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 9
        }
      ],
      "manufacturerPartsList": {
        "parts": 76,
        "scope": "Mark 23 pistol (single list in the manual; covers 12-rd and 10-rd magazine parts). No other variant lists. Exploded diagram on p.47."
      },
      "partsDiagrams": [],
      "materials": [],
      "note": "The components the procedures above separate. Coating, masking and cure are outside this database; follow your coating system's instructions. A part the manufacturer marks \"factory fit\" should not be swapped or reworked."
    },
    {
      "id": "reassemble",
      "title": "Reassemble",
      "videos": [],
      "procedures": [
        {
          "procedure": "reassembly",
          "title": "Reassembly",
          "configuration": false,
          "steps": [
            {
              "n": 1,
              "instruction": "Insert the muzzle of the barrel through the large hole in the front of the slide."
            },
            {
              "n": 2,
              "instruction": "Drop the barrel down into the slide and push it forward until the O-ring engages the slide, the locking block fits within the ejection port, and the angled locking surfaces of the locking block are visible along the bottom of the slide.",
              "tip": "The O-ring will then hold the muzzle tight in the front of the slide. If the barrel feels loose, the O-ring is worn."
            },
            {
              "n": 3,
              "instruction": "Install the captured recoil/buffer spring assembly so the front of the guide rod engages the smaller hole in the front of the slide.",
              "warning": "The larger hole takes the barrel, the smaller one the guide rod."
            },
            {
              "n": 4,
              "instruction": "Align the opposing angled locking surfaces of the recoil spring guide rod with those on the bottom of the barrel locking block."
            },
            {
              "n": 5,
              "instruction": "Push the rear of the recoil/buffer spring assembly forward far enough that the recoil spring retainer engages the shelf on the front of the barrel locking block."
            },
            {
              "n": 6,
              "instruction": "Hold the slide with your thumb keeping the rear of the recoil/buffer spring assembly in place."
            },
            {
              "n": 7,
              "instruction": "Hold the frame in the other hand and position the rear of the slide above the front edge of the frame."
            },
            {
              "n": 8,
              "instruction": "Draw the slide back onto the frame so the rails of the locking insert and guiding part run within the grooves in the slide."
            },
            {
              "n": 9,
              "instruction": "Retract the slide until the recess in its left side is centred on the slide release axle hole."
            },
            {
              "n": 10,
              "instruction": "Holding the slide there, insert the slide release from left to right until it is flush with the side of the frame and locks in place."
            },
            {
              "n": 11,
              "instruction": "Reinstall the thread protector by rotating it clockwise until it stops.",
              "warning": "Avoid overtightening — it strips the threads."
            },
            {
              "n": 12,
              "instruction": "Perform a function check."
            }
          ],
          "instruction": null
        }
      ]
    },
    {
      "id": "torque",
      "title": "Torque",
      "coverage": "none-recorded",
      "manufacturer": [],
      "reported": [],
      "notes": "The manufacturer's documents give no torque value. They say: \"Reinstall the thread protector onto the barrel by rotating it clockwise until it stops, avoid overtightening to prevent stripping.\" (Heckler & Koch Mark 23 Operator’s Manual, PDF p. 27 (reassembly step 11)) \"Retighten the rear sight retaining screw.\" (Heckler & Koch Mark 23 Operator’s Manual, PDF p. 16 (windage adjustment))"
    },
    {
      "id": "function-check",
      "title": "Function check",
      "checks": [
        "Verify the pistol is unloaded with no magazine inserted before each check.",
        "With the hammer down, press the trigger for a double-action hammer fall.",
        "Cock the hammer, operate the safety or decocker as fitted, and confirm the expected behaviour.",
        "Rack the slide and press the trigger for a single-action break.",
        "Hold the trigger back, rack the slide, release slowly and confirm the reset.",
        "Confirm the slide locks open on an empty magazine and the magazine drops free.",
        "Confirm the barrel O-ring is present and in good condition."
      ],
      "videos": []
    }
  ],
  "troubleshooting": [
    {
      "symptom": "The barrel sits in the slide but feels loose, or accuracy has fallen off.",
      "cause": "The O-ring near the muzzle is worn or missing. It is what holds the barrel tight in the front of the slide during firing.",
      "fix": "Fit a new O-ring. HK treats it as an inspect-or-replace item at every strip.",
      "damageRisk": "A loose barrel is a accuracy problem, not a safety one, but it will not improve on its own."
    },
    {
      "symptom": "The recoil/buffer spring assembly will not seat.",
      "cause": "The guide rod has been put into the large hole meant for the barrel, or the angled locking surfaces are not aligned with those on the barrel locking block.",
      "fix": "The barrel goes through the large hole, the guide rod into the smaller one. Then align the opposing angled surfaces and push the rear of the assembly forward until the retainer catches the shelf on the locking block."
    },
    {
      "symptom": "The slide release will not go back in.",
      "cause": "The recess in the left side of the slide is not centred on the axle hole.",
      "fix": "Retract the slide until the recess lines up, hold it, and insert the slide release left to right until flush and locked."
    },
    {
      "symptom": "The thread protector will not thread back on, or spins without tightening.",
      "cause": "It has been cross-threaded or overtightened previously.",
      "fix": "Start it by hand counter-clockwise until you feel it drop into the thread, then turn clockwise until it stops. Do not force it.",
      "damageRisk": "HK warns overtightening strips the threads."
    }
  ],
  "sources": [
    {
      "n": 1,
      "id": "hk-mark23-manual",
      "title": "Heckler & Koch Mark 23 Operator’s Manual",
      "publisher": "Heckler & Koch",
      "reliability": "primary",
      "url": "https://hk-usa.com/wp-content/uploads/2026/08/Mark-23-Operators-Manual-8.25.26-FINAL.pdf",
      "accessed": "2026-09-15"
    }
  ]
}