{
  "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": "swiss-k31",
    "name": "Schmidt-Rubin K31",
    "manufacturer": {
      "id": "swiss-waffenfabrik",
      "name": "Waffenfabrik Bern"
    },
    "category": "rifle",
    "action": "bolt-action",
    "calibers": [
      "7.5x55mm Swiss (GP11)"
    ],
    "alsoKnownAs": [
      "Karabiner Modell 1931",
      "K31"
    ],
    "coversAlso": [
      "Schmidt-Rubin Model 1911 rifle and carbine (longer action, same straight-pull principle)"
    ],
    "page": "firearms/swiss-k31.html",
    "bundle": "api/v1/firearms/swiss-k31.json",
    "lastUpdated": "2026-10-29"
  },
  "notices": [
    "This work order is written for the Schmidt-Rubin K31. It is reported to cover Schmidt-Rubin Model 1911 rifle and carbine (longer action, same straight-pull principle) — 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": "medium",
    "verification": "community-reviewed"
  },
  "manufacturerDisassembly": {
    "status": "not-recorded",
    "limit": null,
    "statement": null,
    "source": null
  },
  "recalls": [],
  "shopTier": {
    "tier": 1,
    "group": "rifle",
    "rating": "Pew-Takedown editorial rating (1 easy – 3 hardest), not the manufacturer's",
    "reason": "Few parts. The barrelled action comes out of the stock after the bands and two screws, and the straight-pull bolt splits into four sub-assemblies by hand. The bolt handle lug carries the striker spring, so bolt reassembly is the only fiddly step, and I found no source reporting it as a trap.",
    "confidence": "low",
    "partCount": null,
    "painPoints": [
      {
        "issue": "The bolt handle's lug rides in the locking collar's helical slot and compresses the striker spring. Reassembling the bolt means seating that lug against spring load in the right slot.",
        "during": "reassembly",
        "source": {
          "title": "A look inside the Swiss K31 Bolt",
          "publisher": "The Firearm Blog",
          "reliability": "secondary",
          "url": "https://www.thefirearmblog.com/blog/2013/08/28/swiss-k31-bolt/",
          "page": null,
          "pdfPage": null,
          "pageUrl": null,
          "quote": "When retracted, the bolt handle’s square lug compresses the striker spring and its round center slides in the helical channel of the collar"
        }
      }
    ],
    "minutes": {
      "strip": 35,
      "rebuild": 50,
      "basis": "estimated",
      "note": "Bands and stock screws, straight-pull bolt into its four sub-assemblies, magazine, trigger, sights.",
      "source": null
    },
    "stripScope": [
      {
        "assembly": "Stock",
        "removes": [
          "barrel bands",
          "handguard",
          "front and rear receiver screws",
          "buttplate"
        ]
      },
      {
        "assembly": "Bolt",
        "removes": [
          "bolt handle/rail",
          "locking collar",
          "bolt head and extractor",
          "firing pin assembly and spring",
          "cocking ring"
        ]
      },
      {
        "assembly": "Receiver",
        "removes": [
          "trigger and sear",
          "magazine catch",
          "rear sight"
        ]
      }
    ],
    "hardware": null,
    "specialTools": [
      {
        "tool": "hollow-ground screwdrivers",
        "usedFor": "Military screws"
      }
    ],
    "fitOnRebuild": [
      {
        "check": "Bolt locks and cocks",
        "why": "The handle lug has to be correctly seated in the collar cam. Standard check, not sourced.",
        "source": null
      },
      {
        "check": "Re-zero sights or scope",
        "why": "Sights and optics come off for coating, and point of impact must be re-confirmed. This is a standard check, so no source.",
        "source": null
      }
    ],
    "assessed": "2026-10-29"
  },
  "videos": [],
  "configurations": [],
  "tools": [
    {
      "name": "Bore guide",
      "required": true,
      "usedFor": "Cleaning from the breech without wearing the throat or the crown. On a surplus rifle the crown is often the difference between accuracy and none."
    }
  ],
  "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 catch and remove the magazine.",
          "partsFreed": [
            "Magazine"
          ]
        },
        {
          "n": 3,
          "instruction": "Pull the bolt straight rearward to extract and eject any chambered round."
        },
        {
          "n": 4,
          "instruction": "Inspect the chamber and magazine well with a light and physically confirm the chamber is empty.",
          "warning": "Straight-pull or not, the chamber check is the same."
        },
        {
          "n": 5,
          "instruction": "Remove all live ammunition from the work area."
        }
      ],
      "videos": []
    },
    {
      "id": "disassemble",
      "title": "Disassemble",
      "videos": [],
      "procedures": [
        {
          "procedure": "field-strip",
          "title": "Field Strip — Bolt Removal",
          "level": "field-strip",
          "configuration": false,
          "steps": [
            {
              "n": 1,
              "instruction": "Complete the Clear and Make Safe procedure."
            },
            {
              "n": 2,
              "instruction": "Pull the bolt straight rearward to its rearmost position."
            },
            {
              "n": 3,
              "instruction": "Press the bolt release catch on the left rear of the receiver and withdraw the bolt straight rearward out of the action.",
              "warning": "Do not attempt to rotate the bolt handle. This is a straight-pull.",
              "partsFreed": [
                "Bolt assembly"
              ]
            },
            {
              "n": 4,
              "instruction": "Clean the bore from the breech using a bore guide, and clean the bolt face, lugs, and chamber.",
              "warning": "Always use a bore guide on a surplus rifle. Cleaning rod wear at the crown is a permanent accuracy loss and is very common on milsurp."
            },
            {
              "n": 5,
              "instruction": "Stop here for routine maintenance. Bolt disassembly is a separate procedure and is not part of normal cleaning."
            }
          ]
        }
      ]
    },
    {
      "id": "refinish",
      "title": "Refinish",
      "components": [
        {
          "name": "Bolt assembly",
          "procedure": "field-strip",
          "level": "field-strip",
          "step": 3
        }
      ],
      "manufacturerPartsList": null,
      "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": "Align the bolt with the receiver raceway."
            },
            {
              "n": 2,
              "instruction": "Slide the bolt straight forward into the receiver until it passes the release catch."
            },
            {
              "n": 3,
              "instruction": "Cycle the bolt straight back and forward several times to confirm smooth travel and correct locking."
            },
            {
              "n": 4,
              "instruction": "Reinstall the magazine and perform the function check."
            }
          ],
          "instruction": null
        }
      ]
    },
    {
      "id": "torque",
      "title": "Torque",
      "coverage": "none-recorded",
      "manufacturer": [],
      "reported": [],
      "notes": null
    },
    {
      "id": "function-check",
      "title": "Function check",
      "checks": [
        "Verify the rifle is unloaded — chamber and magazine — before each check.",
        "Cycle the bolt and confirm it cocks and closes fully into battery.",
        "With the action cocked, engage the safety and press the trigger. The striker must not release.",
        "Disengage the safety without touching the trigger. The striker must not release.",
        "Press the trigger and confirm the striker releases with a firm snap.",
        "Load dummy rounds and confirm they feed and eject cleanly.",
        "If you have any doubt about the rifle’s history, have headspace gauged by a gunsmith before firing live ammunition.",
        "Confirm the bolt locks positively at the end of its forward stroke — on a straight-pull the locking happens as you push the handle home, and it should feel definite."
      ],
      "videos": []
    }
  ],
  "troubleshooting": [],
  "sources": [
    {
      "n": 1,
      "id": null,
      "title": "Karabiner 31 Handbook",
      "publisher": "Swiss Army",
      "reliability": "primary",
      "url": null,
      "accessed": null
    },
    {
      "n": 2,
      "id": "tier-733a4309",
      "title": "A look inside the Swiss K31 Bolt",
      "publisher": "The Firearm Blog",
      "reliability": "secondary",
      "url": "https://www.thefirearmblog.com/blog/2013/08/28/swiss-k31-bolt/",
      "accessed": "2026-10-29"
    }
  ]
}