{ "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": "sig-p320", "name": "SIG Sauer P320", "manufacturer": { "id": "sig-sauer", "name": "SIG Sauer" }, "category": "pistol", "action": "striker-fired-short-recoil", "calibers": [ "9x19mm Parabellum", ".40 S&W", ".357 SIG", ".45 ACP" ], "alsoKnownAs": [ "M17", "M18", "P320 X-Carry", "P320 Compact" ], "coversAlso": [ "SIG Sauer M17", "SIG Sauer M18", "P320 Compact", "P320 X-Series", "P320 XTEN" ], "page": "firearms/sig-p320.html", "bundle": "api/v1/firearms/sig-p320.json", "lastUpdated": "2026-10-29" }, "notices": [ "SIG Sauer safety notice — P320 Voluntary Upgrade Program (2017): All SIG SAUER P320 pistols purchased before August 2017, i.e. without the upgraded trigger, sear, striker and mechanical disconnector; P320s made after 2017-08-08 already include the upgraded design. SIG's online serial-number lookup shows whether a given pistol has been upgraded. Voluntary, free upgrade (SIG pays shipping both ways): register online at sigsauer.com/support/p320-voluntary-upgrade/ (serial-number lookup) or call SIG SAUER Customer Service (603) 610-3000 option 1; the pistol is returned with lighter trigger/sear/striker and a mechanical disconnector.", "SIG Sauer limits owner disassembly: Field strip, magazine disassembly, and the section 8 user procedures, including removing the Fire Control Unit from the grip module. The FCU itself is not to be disassembled.", "This work order is written for the SIG Sauer P320. It is reported to cover SIG Sauer M17; SIG Sauer M18; P320 Compact; P320 X-Series; P320 XTEN — if the firearm on the bench is one of those, check the torque notes: values do not always carry over." ], "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": "limited", "limit": "Field strip, magazine disassembly, and the section 8 user procedures, including removing the Fire Control Unit from the grip module. The FCU itself is not to be disassembled.", "statement": "SIG says not to disassemble the P320 beyond the point explained in the manual; further disassembly is restricted to a certified SIG SAUER armorer or professional gunsmith, and ignoring this voids the warranty. No further disassembly of the FCU is authorized.", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "5", "pdfPage": 5, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=5", "quote": "Do not attempt to disassemble your SIG SAUER firearm beyond the point explained in this manual. Disassembly beyond the instructions in this manual is restricted to a certified SIG SAUER armorer or professional gunsmith. Failure to comply with these restrictions will void your warranty." } }, "recalls": [ { "title": "P320 Voluntary Upgrade Program", "issued": "2017", "affected": "All SIG SAUER P320 pistols purchased before August 2017, i.e. without the upgraded trigger, sear, striker and mechanical disconnector; P320s made after 2017-08-08 already include the upgraded design. SIG's online serial-number lookup shows whether a given pistol has been upgraded.", "hazard": "SIG states the upgrade 'will enhance the protection against unintended discharges if the pistol is dropped' and that any unintended discharge, including from a dropped firearm, carries a risk of death or serious bodily injury; the added mechanical disconnector also protects against cartridge-failure events and prevents a dead trigger if the trigger is pulled with the slide retracted.", "action": "Voluntary, free upgrade (SIG pays shipping both ways): register online at sigsauer.com/support/p320-voluntary-upgrade/ (serial-number lookup) or call SIG SAUER Customer Service (603) 610-3000 option 1; the pistol is returned with lighter trigger/sear/striker and a mechanical disconnector.", "status": "upgrade-available", "source": { "title": "SIG SAUER — Voluntary Upgrade Notice (P320 upgrade program customer letter)", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/pub/media/sigsauer/resources/Voluntary-Upgrade-Notice-1.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "This upgrade program has been available to all P320 owners since August 2017, and it remains available to all P320 owners who purchased their pistols before that date. The upgrade program is completely free of charge to all customers; SIG SAUER is even covering the cost of shipping and returning your P320 pistol to you! [...] These upgrades will enhance the protection against unintended discharges if the pistol is dropped." } } ], "shopTier": { "tier": 1, "group": "pistol", "rating": "Pew-Takedown editorial rating (1 easy – 3 hardest), not the manufacturer's", "reason": "The coatable parts come off as units: the fire control unit lifts out of the polymer grip module in the owner procedure and stays assembled (SIG reserves the sear housing for depot), leaving a slide with striker, extractor and sights. Only order matters (slide off before the takedown lever).", "confidence": "high", "partCount": null, "painPoints": [ { "issue": "If the takedown lever is pulled before the slide is off, the fire control unit lifts out with the slide and the two lock together.", "during": "disassembly", "source": { "title": "Seeking stupidity relief: P320 FCU stuck on slide. (Don't remove the takedown lever first!) - Topic", "publisher": "SIGforum", "reliability": "anecdotal", "url": "https://sigforum.com/eve/forums/a/tpc/f/430601935/m/6910085464", "page": null, "pdfPage": null, "pageUrl": null, "quote": "If one removes the P320 takedown lever before removing the slide, the fire control unit comes along with the slide when it’s lifted up, and then they can’t be separated." } }, { "issue": "If the FCU itself is opened, every pin pushes except the sear housing spirol pin, which must be driven with the unit supported, and the takedown safety lever spring needs a 90-degree pick.", "during": "both", "source": { "title": "Building a P320 FCU from parts - Topic", "publisher": "SIGforum", "reliability": "anecdotal", "url": "https://sigforum.com/eve/forums/a/tpc/f/430601935/m/3440076374?csra=Y&f=430601935&a=tpc&m=3440076374&s=674608412", "page": null, "pdfPage": null, "pageUrl": null, "quote": "All P320 pins push in easily except for the Spirol (roll) pin that must be driven through the Sear Housing." } }, { "issue": "SIG restricts disassembly past the manual to its armorers or a professional gunsmith.", "during": "both", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Disassembly beyond the instructions in this manual is restricted to a certified SIG SAUER armorer or professional gunsmith." } } ], "minutes": { "strip": 15, "rebuild": 20, "basis": "estimated", "note": "Slide (striker assembly, extractor, sights, optic plate) and FCU out of the grip module as a unit; rebuild is striker and FCU back in plus function check.", "source": null }, "stripScope": [ { "assembly": "Slide", "removes": [ "slide cover plate", "striker assembly", "extractor, spring and pin", "rear sight", "front sight" ], "tools": [ "pin punch", "sight pusher" ] }, { "assembly": "Grip module / FCU", "removes": [ "takedown lever", "fire control unit (as a unit)", "slide catch lever and spring (if FCU opened)" ], "tools": [ "90-degree pick" ] } ], "hardware": null, "specialTools": [ { "tool": "90-degree pick", "usedFor": "Takedown safety lever spring" }, { "tool": "FCU support block (e.g. Gray Guns)", "usedFor": "Driving the sear housing pin if the FCU is opened" }, { "tool": "dovetail sight pusher (or brass drift and padded vise)", "usedFor": "Removing and refitting dovetailed sights for coating" } ], "fitOnRebuild": [ { "check": "FCU fully seated in the grip module", "why": "A partly seated FCU gives a gritty trigger or no reset", "source": null }, { "check": "Function check: trigger reset, sear/striker engagement, safeties", "why": "Standard post-reassembly check on any pistol whose fire-control parts were removed; a mis-seated spring shows up here, not on the bench", "source": null } ], "assessed": "2026-10-29" }, "videos": [ { "title": "P320 Field Strip and Cleaning with Chris Cavallaro", "url": "https://www.youtube.com/watch?v=pUV6T_GB6To", "platform": "youtube", "embedUrl": null, "shows": [ "field-strip", "cleaning", "maintenance", "reassembly" ], "appliesTo": null, "published": "2021-05-20", "note": null, "channel": { "id": "UCvoH9K7l8MTVs6NO6KybLUA", "name": "SIG SAUER Academy", "url": "https://www.youtube.com/@SIGSAUERACDY", "owner": "SIG SAUER Academy (SIG SAUER, Inc. training division; site footer '© SIG SAUER 2026', logins via auth.sigsauer.com)" }, "accessed": "2026-10-15" } ], "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 and lock it open with the slide catch lever." }, { "n": 4, "instruction": "Visually and physically verify the chamber is empty." }, { "n": 5, "instruction": "Remove all live ammunition from the work area." } ], "videos": [] }, { "id": "disassemble", "title": "Disassemble", "videos": [ { "title": "P320 Field Strip and Cleaning with Chris Cavallaro", "url": "https://www.youtube.com/watch?v=pUV6T_GB6To", "platform": "youtube", "embedUrl": null, "shows": [ "field-strip", "cleaning", "maintenance", "reassembly" ], "appliesTo": null, "published": "2021-05-20", "note": null, "channel": { "id": "UCvoH9K7l8MTVs6NO6KybLUA", "name": "SIG SAUER Academy", "url": "https://www.youtube.com/@SIGSAUERACDY", "owner": "SIG SAUER Academy (SIG SAUER, Inc. training division; site footer '© SIG SAUER 2026', logins via auth.sigsauer.com)" }, "accessed": "2026-10-15" } ], "procedures": [ { "procedure": "field-strip", "title": "Field Strip", "level": "field-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Complete the Clear and Make Safe procedure and leave the slide locked to the rear." }, { "n": 2, "instruction": "Rotate the takedown lever on the right side of the frame downward about 90 degrees until it stops.", "tip": "On some pistols the lever is stiff when new. Thumb pressure, not tools." }, { "n": 3, "instruction": "Hold the slide, release the slide catch lever, and ease the slide forward off the frame.", "partsFreed": [ "Slide assembly" ] }, { "n": 4, "instruction": "Lift the recoil spring assembly out of the inverted slide.", "warning": "It is under spring tension — keep a thumb on it.", "partsFreed": [ "Recoil spring assembly" ] }, { "n": 5, "instruction": "Lift the barrel up and out of the slide.", "partsFreed": [ "Barrel" ] } ] }, { "procedure": "remove-fire-control-unit", "title": "Remove the Fire Control Unit", "level": "detail-strip", "configuration": false, "steps": [ { "n": 1, "instruction": "Field strip the pistol and set the slide, barrel, and recoil spring assembly aside." }, { "n": 2, "instruction": "With the takedown lever still rotated down, grasp the takedown lever and lift the fire control unit up and out of the grip module.", "tip": "It lifts out rear-first on most grip modules.", "partsFreed": [ "Fire control unit" ] } ] } ] }, { "id": "refinish", "title": "Refinish", "components": [ { "name": "Slide assembly", "procedure": "field-strip", "level": "field-strip", "step": 3 }, { "name": "Recoil spring assembly", "procedure": "field-strip", "level": "field-strip", "step": 4 }, { "name": "Barrel", "procedure": "field-strip", "level": "field-strip", "step": 5 }, { "name": "Fire control unit", "procedure": "remove-fire-control-unit", "level": "detail-strip", "step": 2 } ], "manufacturerPartsList": null, "partsDiagrams": [], "materials": [ { "component": "Grip module", "material": "Glass reinforced", "finish": null, "appliesTo": "all P320 models (manual 13.0)", "note": null, "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Glass reinforced grip module or, alloy steel with integral accessory rail." } }, { "component": "Grip module", "material": "alloy steel", "finish": null, "appliesTo": "P320 models with a metal grip module (models not named)", "note": null, "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Glass reinforced grip module or, alloy steel with integral accessory rail." } }, { "component": "Slide", "material": "stainless steel", "finish": null, "appliesTo": "all P320 models (manual 13.0)", "note": null, "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Solid high-strength stainless steel slide with front and rear cocking serrations." } }, { "component": "Frame (serialized fire-control unit)", "material": "Stainless Steel", "finish": null, "appliesTo": "P320", "note": null, "source": { "title": "SIG SAUER, Inc. — 2019 GDS CATLOG WORKING FINAL LR", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/pub/media/sigsauer/resources/2019_GDS_CATLOG_WORKING-FINAL-LR.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Serialized Stainless Steel Frame" } }, { "component": "Whole firearm", "material": null, "finish": "NITRON", "appliesTo": "P320 Full Size, item 320F-9-B", "note": "The maker states this for the firearm as a whole, not for a named part.", "source": { "title": "SIG SAUER, Inc. — 2021 Guide Price List 11 8", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/2021-Guide-Price-List-11-8.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "P320, 9MM, 4.7IN, NITRON, BLK, DAO, CONTRAST SIGHTS, MODULAR POLYMER GRIP, (2) 17RD STEEL MAG, RAIL" } }, { "component": "Magazine", "material": "STEEL", "finish": null, "appliesTo": "P320 Full Size, item 320F-9-B", "note": null, "source": { "title": "SIG SAUER, Inc. — 2021 Guide Price List 11 8", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/2021-Guide-Price-List-11-8.pdf", "page": null, "pdfPage": null, "pageUrl": null, "quote": "P320, 9MM, 4.7IN, NITRON, BLK, DAO, CONTRAST SIGHTS, MODULAR POLYMER GRIP, (2) 17RD STEEL MAG, RAIL" } } ], "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": [ { "title": "P320 Field Strip and Cleaning with Chris Cavallaro", "url": "https://www.youtube.com/watch?v=pUV6T_GB6To", "platform": "youtube", "embedUrl": null, "shows": [ "field-strip", "cleaning", "maintenance", "reassembly" ], "appliesTo": null, "published": "2021-05-20", "note": null, "channel": { "id": "UCvoH9K7l8MTVs6NO6KybLUA", "name": "SIG SAUER Academy", "url": "https://www.youtube.com/@SIGSAUERACDY", "owner": "SIG SAUER Academy (SIG SAUER, Inc. training division; site footer '© SIG SAUER 2026', logins via auth.sigsauer.com)" }, "accessed": "2026-10-15" } ], "procedures": [ { "procedure": "remove-fire-control-unit", "title": "Remove the Fire Control Unit", "configuration": false, "steps": [ { "n": 3, "instruction": "To install into another grip module, seat the front of the fire control unit first, then press the rear down until it sits flush." }, { "n": 4, "instruction": "Confirm the fire control unit is fully seated and the takedown lever rotates freely before reassembling the slide.", "warning": "A partially seated fire control unit can bind the trigger. Verify with a function check." } ], "instruction": null }, { "procedure": "reassembly", "title": "Reassembly", "configuration": false, "steps": [ { "n": 1, "instruction": "Set the barrel into the inverted slide and seat it fully forward." }, { "n": 2, "instruction": "Seat the recoil spring assembly into the cut in the barrel lug and press it down into the slide channel." }, { "n": 3, "instruction": "Set the slide onto the frame rails and push it rearward until the slide catch lever will lock it open." }, { "n": 4, "instruction": "With the slide locked back, rotate the takedown lever up to horizontal." }, { "n": 5, "instruction": "Release the slide and perform the function check." } ], "instruction": null } ] }, { "id": "torque", "title": "Torque", "coverage": "sourced", "manufacturer": [ { "fastener": "Sight plate screws (2, rear sight/sight plate, 3/32 in. hex, from bottom of slide)", "appliesTo": "SIG P320 pistols", "qualifier": "exact", "value": 20, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.3, "in-lb": 20, "ft-lb": 1.7 }, "valueMax": null }, "sequence": "Install LCI post and spring into slide; install sight plate and sight onto slide holding LCI post and spring in place; insert sight plate screws from bottom of slide and tighten to 20 in-lbf; then reinstall striker assembly, extractor, extractor pin/spring/plus pin and rear slide cap. Note: 'Sight plate screws are for securing the rear sight and sight plate only.' 8.1 table also lists 20 in-lbf / 2.26 nm.", "threadlocker": "LOCTITE 243 (per 8.1 table; 'If there is no Nylok® patch present on the fastener, use specified Loctite®')", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "81", "pdfPage": 81, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=81", "quote": "3. Insert sight plate screws into the bottom of slide and tighten to 20 in-lbf using a 3/32 in. Hex drive bit." } }, { "fastener": "Blanking (optic cover) plate screws (2, T20, top of slide)", "appliesTo": "SIG P320 optic-cut slides", "qualifier": "exact", "value": 20, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.3, "in-lb": 20, "ft-lb": 1.7 }, "valueMax": null }, "sequence": "Place blanking plate into its slot in slide; insert blanking plate screws and tighten. Note: 'Blanking plate screws are for securing the blanking plate only.' CONFLICT: the section 8.1 torque table (p. 77) lists Blanking Plate Screws at 25 in-lbf / 2.82 nm.", "threadlocker": "LOCTITE 243 (per 8.1 table; 'If there is no Nylok® patch present on the fastener, use specified Loctite®')", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "85", "pdfPage": 85, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=85", "quote": "2. Insert blanking plate screws and tighten to 20 in-lbf using a T20 drive bit." } }, { "fastener": "ROMEO red dot mounting screws (2, 1/8 in. hex)", "appliesTo": "SIG P320 pistols equipped with a SIG ROMEO optic (with or without shroud)", "qualifier": "exact", "value": 25, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.8, "in-lb": 25, "ft-lb": 2.1 }, "valueMax": null }, "sequence": "Insert ROMEO into shroud (if equipped); place ROMEO and shroud assembly on slide aligning holes; install ROMEO screws and torque to 25 in-lbs; refer to ROMEO manual for zeroing. 8.1 table also lists 25 in-lbf / 2.82 nm.", "threadlocker": "LOCTITE 243 (per 8.1 table; 'If there is no Nylok® patch present on the fastener, use specified Loctite®')", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "88", "pdfPage": 88, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=88", "quote": "3. Install ROMEO screws with 1/8 in. Hex drive bit and torque to 25 in-lbs." } }, { "fastener": "Compensator attachment screws (2, T10)", "appliesTo": "SIG P320 models with factory barrel compensator", "qualifier": "exact", "value": 20, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.3, "in-lb": 20, "ft-lb": 1.7 }, "valueMax": null }, "sequence": "Clean and degrease threads of barrel and compensator. Insert barrel into slide. Apply LOCTITE 246 to threads of barrel and compensator. Thread compensator onto the barrel until it stops, then unscrew until vertical slots in barrel align with the screw holes in the compensator. Install compensator attachment screws and apply a final torque of 20 in-lbf. (8.1 table: Barrel Compensator Threads N/A torque, LOCTITE 246.)", "threadlocker": "LOCTITE 243 on screws; LOCTITE 246 on barrel/compensator threads (8.1 table)", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "94", "pdfPage": 94, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=94", "quote": "4. Install compensator attachment screws into compensator using a T10 drive bit and apply a final torque of 20 in-lbf." } }, { "fastener": "Magazine funnel screw, standard funnel (T10, rear of grip module)", "appliesTo": "SIG P320 grip modules with detachable standard magazine funnel", "qualifier": "exact", "value": 6, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 0.68, "in-lb": 6, "ft-lb": 0.5 }, "valueMax": null }, "sequence": null, "threadlocker": "LOCTITE 243 (per 8.1 table; 'If there is no Nylok® patch present on the fastener, use specified Loctite®')", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "100", "pdfPage": 100, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=100", "quote": "For standard magazine funnel screw, use a T10 drive bit to thread funnel screw into rear of grip module and tighten to 6 in-lbf." } }, { "fastener": "Magazine funnel screw, AXG magazine well (T10, bottom of grip module)", "appliesTo": "SIG P320 AXG grip modules", "qualifier": "exact", "value": 11, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.2, "in-lb": 11, "ft-lb": 0.92 }, "valueMax": null }, "sequence": null, "threadlocker": "LOCTITE 243 (per 8.1 table; 'If there is no Nylok® patch present on the fastener, use specified Loctite®')", "source": { "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "page": "100", "pdfPage": 100, "pageUrl": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf#page=100", "quote": "For AXG magazine funnel screw, use a T10 drive bit to thread funnel screw into bottom of grip module and tighten to 11 in-lbf." } } ], "reported": [ { "fastener": "Optic mounting screws through plate (T15 6-40 x 9/16)", "appliesTo": "SIG P320 (not M17/M18, not integrated-plate slides) with Forward Controls Design OPF-P320, RMR plate, Trijicon RMR", "qualifier": "range", "value": 13, "valueMax": 15, "unit": "in-lb", "converted": { "value": { "N-m": 1.5, "in-lb": 13, "ft-lb": 1.1 }, "valueMax": { "N-m": 1.7, "in-lb": 15, "ft-lb": 1.2 } }, "sequence": null, "threadlocker": null, "source": { "title": "OPF-P320, RMR (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-P320-RMR_p_449.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque value for T15 6-40 x 9/16 screws: 13 to 15 in lb." } }, { "fastener": "Optic plate to slide screws", "appliesTo": "SIG P320 X-Five Legion, Legion Carry, commercial M17/M18 and Romeo1 Pro/DPP-cut slides with FCD OPF-P320, RMR, RSD plate", "qualifier": "exact", "value": 12, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.4, "in-lb": 12, "ft-lb": 1 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "OPF-P320, RMR, RSD (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-P320-RMR-RSD_p_344.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Plate to slide: 12 in·lb" } }, { "fastener": "Optic (sight) to plate screws", "appliesTo": "SIG P320 R1P/DPP-cut slides with FCD OPF-P320, RMR, RSD plate, Trijicon RMR", "qualifier": "exact", "value": 12, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.4, "in-lb": 12, "ft-lb": 1 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "OPF-P320, RMR, RSD (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-P320-RMR-RSD_p_344.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Sight to plate: 12 in·lb" } }, { "fastener": "Optic plate to slide screws (M4 x 0.7 x 6 mm)", "appliesTo": "Military-issue M17/M18 (P320 variant) with Forward Controls Design OPF-M17, ACRO plate", "qualifier": "exact", "value": 20, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.3, "in-lb": 20, "ft-lb": 1.7 }, "valueMax": null }, "sequence": null, "threadlocker": "VC-3 packet supplied", "source": { "title": "OPF-M17, ACRO (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-M17-ACRO_p_277.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "OPF-M17-ACRO is shipped with two M4 0.7mm x 6mm (torque value: 20 in·lb) and a packet of VC-3." } }, { "fastener": "Aimpoint ACRO P1/P2 mounting screw", "appliesTo": "Military-issue M17/M18 with FCD OPF-M17, ACRO plate, Aimpoint ACRO P1/P2", "qualifier": "exact", "value": 26, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2.9, "in-lb": 26, "ft-lb": 2.2 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "OPF-M17, ACRO (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-M17-ACRO_p_277.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque value for ACRO P1/P2 mounting screw: 26 in·lb. For Steiner MPS, 18 in·lb. (updated by Steiner in 2024)" } }, { "fastener": "Steiner MPS mounting screw", "appliesTo": "Military-issue M17/M18 with FCD OPF-M17, ACRO plate, Steiner MPS", "qualifier": "exact", "value": 18, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 2, "in-lb": 18, "ft-lb": 1.5 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "OPF-M17, ACRO (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-M17-ACRO_p_277.html", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque value for ACRO P1/P2 mounting screw: 26 in·lb. For Steiner MPS, 18 in·lb. (updated by Steiner in 2024)" } }, { "fastener": "Optic adapter plate mounting screws (Holosun RMR-footprint plate for P320 Romeo1 Pro cut)", "appliesTo": "SIG P320 with Romeo1 Pro optic cut, HOLOSUN adapter plate for RMR footprint (407C/507C/508T/SRO)", "qualifier": "exact", "value": 1.4, "valueMax": null, "unit": "N-m", "converted": { "value": { "N-m": 1.4, "in-lb": 12, "ft-lb": 1 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "Adapter plate for Footprint RMR on SIG P320 Romeo 1 Pro (product page)", "publisher": "HOLOSUN Europe (holosun.eu, operated by Picotronic GmbH, HOLOSUN European distributor)", "reliability": "secondary", "url": "https://www.holosun.eu/en/p/70189674", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Tightening torque recommended: 1,4 Nm" } }, { "fastener": "Optic adapter plate mounting screws (Holosun RMR-footprint plate for P320 Romeo1 Pro cut)", "appliesTo": "SIG P320 with Romeo1 Pro optic cut, HOLOSUN adapter plate for RMR footprint (407C/507C/508T/SRO)", "qualifier": "maximum", "value": 1.7, "valueMax": null, "unit": "N-m", "converted": { "value": { "N-m": 1.7, "in-lb": 15, "ft-lb": 1.3 }, "valueMax": null }, "sequence": null, "threadlocker": null, "source": { "title": "Adapter plate for Footprint RMR on SIG P320 Romeo 1 Pro (product page)", "publisher": "HOLOSUN Europe (holosun.eu, operated by Picotronic GmbH, HOLOSUN European distributor)", "reliability": "secondary", "url": "https://www.holosun.eu/en/p/70189674", "page": null, "pdfPage": null, "pageUrl": null, "quote": "tightening torque Maximum: 1,7 Nm" } }, { "fastener": "Red-dot optic mounting screws (6-32 flat head, supplied) into EGW rear-dovetail sight mount", "appliesTo": "SIG Sauer P320 (non-optics-ready slide with rear dovetail) with the EGW 'Trijicon RMR / SRO, Holosun 407c / 507c Mount for Sig Sauer P220, P226, P229, P320' (replaces the rear sight; for Trijicon RMR/", "qualifier": "exact", "value": 15, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.7, "in-lb": 15, "ft-lb": 1.2 }, "valueMax": null }, "sequence": "Remove the rear sight, install the EGW mount in the dovetail, tighten the set screw if applicable, place the optic on the mount, then apply blue Loctite and torque the optic screws.", "threadlocker": "Blue Loctite on the provided mounting screws (EGW instructions)", "source": { "title": "Trijicon RMR / SRO, Holosun 407c / 507c Mount for Sig Sauer P220, P226, P229, P320 (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/trijicon-rmr-sro-holosun-407c-507c-mount-for-sig-sauer-p220-p226-p229-p320", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque mounting screws to 15in/lbs" } }, { "fastener": "Red-dot optic mounting screws (supplied) into EGW rear-dovetail sight mount (Docter/Venom/Viper/FastFire footprint)", "appliesTo": "SIG Sauer P320 (non-optics-ready slide with rear dovetail) with the EGW 'SIG Sauer P220 P226 P229 P320 Red Dot Mount | Fits Vortex Venom, Viper & Burris FastFire | EGW' (replaces the rear sight)", "qualifier": "exact", "value": 15, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.7, "in-lb": 15, "ft-lb": 1.2 }, "valueMax": null }, "sequence": "Remove the rear sight, install the EGW mount in the dovetail, tighten the set screw if applicable, place the optic on the mount, then apply blue Loctite and torque the optic screws.", "threadlocker": "Blue Loctite on the provided mounting screws (EGW instructions)", "source": { "title": "SIG Sauer P220 P226 P229 P320 Red Dot Mount | Fits Vortex Venom, Viper & Burris FastFire | EGW (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/vortex-viper-venom-sig-sauer-p220-p226-p229-p320-sight-mount-fits-burris-fastfire-and-docter", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque mounting screws to 15 in/lbs" } }, { "fastener": "Vortex Venom mounting screws on EGW adapter plate (Romeo1-cut optics-ready slide)", "appliesTo": "SIG Sauer P320 RX / P320 X-Five Optics Ready (Romeo1 cut; not M17 or Romeo1 Pro cut) with the EGW 'Adapter Plate for Sig P320 (Romeo) to Vortex Venom'", "qualifier": "exact", "value": 15, "valueMax": null, "unit": "in-lb", "converted": { "value": { "N-m": 1.7, "in-lb": 15, "ft-lb": 1.2 }, "valueMax": null }, "sequence": null, "threadlocker": "Blue Loctite on the provided mounting screws (EGW instructions)", "source": { "title": "Adapter Plate for Sig P320 (Romeo) to Vortex Venom (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/vortex-venom-adapter-plate-for-optics-ready-sigs-cut-for-the-romeo-1-p320-rx-x-five", "page": null, "pdfPage": null, "pageUrl": null, "quote": "Torque Specs: 15 in/lbs" } } ], "notes": "SIG's P320 manual gives two figures for the blanking (optic cover) plate screws: 25 in-lbf in its torque table and 20 in-lbf in the installation step. The installation step's 20 in-lbf is shown; confirm with SIG if it matters for your slide." }, { "id": "function-check", "title": "Function check", "checks": [ "Verify the pistol is unloaded before each check.", "Rack the slide and press the trigger. The striker should release cleanly.", "Hold the trigger back, rack the slide, release slowly and feel the reset.", "Press the trigger again to confirm the striker releases.", "If the pistol has a manual safety, confirm the trigger is blocked with the safety engaged.", "Confirm the slide locks open on an empty magazine and the magazine drops free." ], "videos": [] } ], "troubleshooting": [], "sources": [ { "n": 1, "id": null, "title": "SIG Sauer P320 Operator's Manual", "publisher": "SIG Sauer, Inc.", "reliability": "primary", "url": null, "accessed": null }, { "n": 2, "id": null, "title": "SIG Sauer P320 Voluntary Upgrade Program notice (2017)", "publisher": "SIG Sauer, Inc.", "reliability": "primary", "url": null, "accessed": null }, { "n": 3, "id": "sig-sauer-180c42", "title": "SIG P320 Pistols Operator's Manual: Handling & Safety Instructions, 8501909-01 REV11 (Sept 2023), section 8", "publisher": "SIG SAUER", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/OPERATORS_MANUAL_P320_8501909-01_REV11_WEB_FILE_1.pdf", "accessed": "2026-09-27" }, { "n": 4, "id": "forward-controls-design-721227", "title": "OPF-P320, RMR (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-P320-RMR_p_449.html", "accessed": "2026-09-27" }, { "n": 5, "id": "forward-controls-design-a8397d", "title": "OPF-P320, RMR, RSD (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-P320-RMR-RSD_p_344.html", "accessed": "2026-09-27" }, { "n": 6, "id": "forward-controls-design-c3c030", "title": "OPF-M17, ACRO (product page)", "publisher": "Forward Controls Design", "reliability": "secondary", "url": "https://www.forwardcontrolsdesign.com/OPF-M17-ACRO_p_277.html", "accessed": "2026-09-27" }, { "n": 7, "id": "holosun-europe-holosun-eu-operated-b-b03398", "title": "Adapter plate for Footprint RMR on SIG P320 Romeo 1 Pro (product page)", "publisher": "HOLOSUN Europe (holosun.eu, operated by Picotronic GmbH, HOLOSUN European distributor)", "reliability": "secondary", "url": "https://www.holosun.eu/en/p/70189674", "accessed": "2026-09-27" }, { "n": 8, "id": "sigsauer-notice-9eb605", "title": "SIG SAUER — Voluntary Upgrade Notice (P320 upgrade program customer letter)", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/pub/media/sigsauer/resources/Voluntary-Upgrade-Notice-1.pdf", "accessed": "2026-10-03" }, { "n": 9, "id": "sigsauer-doc-0298db", "title": "SIG SAUER, Inc. — 2019 GDS CATLOG WORKING FINAL LR", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/pub/media/sigsauer/resources/2019_GDS_CATLOG_WORKING-FINAL-LR.pdf", "accessed": "2026-10-03" }, { "n": 10, "id": "sigsauer-doc-8d5b28", "title": "SIG SAUER, Inc. — 2021 Guide Price List 11 8", "publisher": "SIG SAUER, Inc.", "reliability": "primary", "url": "https://www.sigsauer.com/media/sigsauer/resources/2021-Guide-Price-List-11-8.pdf", "accessed": "2026-10-03" }, { "n": 11, "id": "evolution-gun-works-egw-8862de", "title": "Trijicon RMR / SRO, Holosun 407c / 507c Mount for Sig Sauer P220, P226, P229, P320 (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/trijicon-rmr-sro-holosun-407c-507c-mount-for-sig-sauer-p220-p226-p229-p320", "accessed": "2026-10-11" }, { "n": 12, "id": "evolution-gun-works-egw-7ce4c3", "title": "SIG Sauer P220 P226 P229 P320 Red Dot Mount | Fits Vortex Venom, Viper & Burris FastFire | EGW (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/vortex-viper-venom-sig-sauer-p220-p226-p229-p320-sight-mount-fits-burris-fastfire-and-docter", "accessed": "2026-10-11" }, { "n": 13, "id": "evolution-gun-works-egw-8ce8eb", "title": "Adapter Plate for Sig P320 (Romeo) to Vortex Venom (EGW product page, installation instructions section)", "publisher": "Evolution Gun Works (EGW)", "reliability": "secondary", "url": "https://egwguns.com/vortex-venom-adapter-plate-for-optics-ready-sigs-cut-for-the-romeo-1-p320-rx-x-five", "accessed": "2026-10-11" }, { "n": 14, "id": "tier-28ee3265", "title": "Seeking stupidity relief: P320 FCU stuck on slide. (Don't remove the takedown lever first!) - Topic", "publisher": "SIGforum", "reliability": "anecdotal", "url": "https://sigforum.com/eve/forums/a/tpc/f/430601935/m/6910085464", "accessed": "2026-10-29" }, { "n": 15, "id": "tier-7888078d", "title": "Building a P320 FCU from parts - Topic", "publisher": "SIGforum", "reliability": "anecdotal", "url": "https://sigforum.com/eve/forums/a/tpc/f/430601935/m/3440076374?csra=Y&f=430601935&a=tpc&m=3440076374&s=674608412", "accessed": "2026-10-29" } ] }