Pew-Takedown
Guide only. Educational guide only. Some information comes from non-authoritative sources. Always consult your manufacturer's manual and a licensed gunsmith. Verify your firearm is unloaded before every procedure. Read the full disclaimer.

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Benelli M4

field strip ~4 min · reassembly ~6 min · detail strip ~30 min

Before you begin Verify this firearm is unloaded. Remove the magazine or empty the cylinder or tube, lock the action open, and check the chamber both by sight and by touch. Keep the muzzle in a safe direction and remove all live ammunition from your work area.
What Benelli Armi says about disassembly Benelli's manual strips the M4 to barrel, bolt, trigger group, stock/pistol grip and gas pistons without tools, and does not tell owners to go no further. (M4 Tactical Shotgun Product Manual — Benelli USA / Benelli Armi S.p.A., p. 88 benelliusa.com [3])

Specifications

Manufacturer
Benelli Armi
Origin
Italy
Category
Shotgun
Action
Gas, short-stroke piston
Calibers
12 gauge
Capacity
5+1 or 7+1 depending on configuration
Production
1998–present (in-production)
Also known as
M1014, M4 Super 90, Benelli M4 Tactical

Model-specific safety

Under spring tension

Easily lost parts

Gas pistons · Bolt handle · Trigger group pin · Link

Tools

No tools required for the field strip.

Shop difficulty

Shop tier 2 Tier 2 — moderate among shotguns, for the full job: strip to the parts that get coated and put it back together working. More systems than the inertia guns (twin gas pistons and cylinder plugs, rotating bolt with cam pin, link and recoil spring tube in the stock) and the Marine Corps stops operators at field strip, but each step is a single orientation or held-spring trap rather than timing. Top of Tier 2.

No sourced part count yet.

Bench time: about 60 min to strip, 85 min to rebuild (estimate). Strip of bolt (cam pin, firing pin), twin gas pistons and plugs, trigger group, magazine and stock/receiver extension; rebuild longer for pistons, link alignment and magazine spring seal ring.

What comes off for coating

Special tools

Known pain points

Fit or check on rebuild

This is Pew-Takedown's rating, not the manufacturer's. How tiers are rated. Forum reports are owners' experience, not specifications.

Procedures

Clear and Make Safe

Clear & Make Safe
  1. Point the muzzle in a safe direction and keep your finger off the trigger.
  2. Engage the crossbolt safety at the trigger guard.
  3. Pull the bolt handle rearward to eject any chambered shell and lock the bolt open.
    Removed at this step: Chambered shell, if present
  4. Cycle the action repeatedly, catching each shell as it ejects, until no more shells feed from the magazine tube.
  5. With the action open, inspect the chamber and look up the magazine tube with a light.
    WarningThe chamber AND the tube. A shell hung up in the tube is easy to miss.
  6. Physically confirm the chamber is empty and remove all live ammunition from the work area.

Field Strip

Field Strip
  1. Complete the Clear and Make Safe procedure.
  2. Unscrew the magazine cap from the end of the magazine tube and remove the forend.
    Removed at this step: Magazine cap Forend
  3. Pull the barrel forward off the magazine tube and out of the receiver.
    Removed at this step: Barrel
  4. Withdraw the two gas pistons from their cylinders in the barrel assembly, noting their orientation.
    WarningNote which way each piston faces before it comes out.
    Removed at this step: Gas pistons
  5. Pull the bolt handle out of the bolt.
    Removed at this step: Bolt handle
  6. Slide the bolt assembly forward and out of the receiver.
    Removed at this step: Bolt assembly
  7. Push out the trigger group pin and lift the trigger group out of the receiver.
    Removed at this step: Trigger group

Remove the magazine spring seal ring, spring and follower

Detail Strip

With the bolt forward and the magazine cap off, uses the removed bolt handle as a tool to pry out the magazine spring seal ring, then takes out the magazine spring and follower. The manual says to do this only when absolutely necessary for major cleaning. Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator disassembly, steps 2-5, pp. 30- archive.org [5]

  1. Place the bolt group in the forward position.
  2. Remove accessories such as the sling, targeting devices and lights.
  3. Unscrew the magazine cap counterclockwise as viewed from the front of the weapon.
    WarningMake sure the muzzle end of the magazine points in a safe direction while removing the magazine cap and the magazine spring seal ring. The magazine parts are under considerable spring tension and can injure you or bystanders if released. If the magazine spring seal is worn, it may come out when the cap is removed and eject the magazine spring.
    Removed at this step: Magazine cap
  4. Pull the bolt handle out of the bolt group.
    Removed at this step: Bolt handle
  5. Use the bolt handle to remove the magazine spring seal ring from the magazine tube.
    WarningMake sure the muzzle end of the magazine points in a safe direction while removing the magazine cap and the magazine spring seal ring. The magazine parts are under considerable spring tension and can injure you or bystanders if released. If the magazine spring seal is worn, it may come out when the cap is removed and eject the magazine spring.
    Removed at this step: Magazine spring seal ring
  6. Remove the magazine spring and the follower from the magazine tube.
    TipTap the magazine on a padded surface to get the follower out.
    Removed at this step: Magazine spring Magazine follower

Remove the telescoping buttstock and pistol grip

Detail Strip

With the trigger group out, extends the telescoping buttstock, rotates and slides the stock module off the recoil spring tube, then unscrews the detachable pistol grip from the receiver (pp. 35-37). Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Applies to: M1014 / M4 with the telescoping buttstock and detachable pistol grip

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator disassembly, Extending/Removing archive.org [5]

  1. Remove the trigger group from the receiver (field strip).
    TipThe manual's stock removal starts 'With the trigger guard removed'.
  2. With the buttstock collapsed, grip it with your firing hand and depress the button with your thumb.
  3. Rotate the telescoping buttstock clockwise and pull it to the rear.
  4. When the buttstock is fully extended, rotate it counterclockwise to the vertical position and release the button.
  5. Grip the extended buttstock with your firing hand, depress the button, and keep it fully depressed while you rotate the buttstock module clockwise.
    TipThe manual's note: keep the button completely depressed while removing the buttstock.
  6. Push the buttstock module in to the inscribed line on the recoil tube.
  7. When the forward edge of the buttstock module reaches the inscribed line, rotate the buttstock counterclockwise until the top of the telescoping module lines up with the flat part of the recoil tube.
  8. Pull the telescoping buttstock to the rear off the recoil tube.
    Removed at this step: Telescoping buttstock module
  9. Unscrew the pistol grip counterclockwise until it is free and remove it to the rear over the recoil tube.
    Removed at this step: Pistol grip

Disassemble the bolt group

Detail Strip

Removes the firing pin retaining pin, firing pin and spring, cam pin and bolt head from the bolt carrier (Assembly groups, Bolt group, p. 38). Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly. The extractor, link and bolt handle retaining pin stay in place.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Assembly groups, 1. Bolt group, pp. 38-3 archive.org [5]

  1. Remove the bolt group from the receiver (field strip).
    WarningDo NOT remove the extractor, link or bolt handle retaining pin during operator disassembly. It is not required to remove these parts for operator cleaning or maintenance.
  2. Place a finger over the rear end of the firing pin and remove the firing pin retaining pin from the right side of the bolt carrier.
    Removed at this step: Firing pin retaining pin
  3. Lift the firing pin, with its spring, out of the recess in the rear of the bolt carrier.
    Removed at this step: Firing pin with firing pin spring
  4. Separate the firing pin spring from the firing pin.
    Removed at this step: Firing pin spring Firing pin
  5. Lift or shake the cam pin out of the bolt assembly.
    Removed at this step: Cam pin
  6. Pull the bolt head out of the bolt carrier.
    Removed at this step: Bolt head

Remove the gas cylinder plugs and gas pistons

Detail Strip

Unscrews both gas cylinder plugs with the bolt handle and pushes the gas pistons out of the front of the cylinders (Assembly groups, 2. Barrel, p. 39). Needed only for major cleaning (every 5,000 rounds), or when water, debris or heavy fouling stops the pistons moving freely. Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Assembly groups, 2. Barrel, pp. 39-40 archive.org [5]

  1. Remove the barrel from the receiver (field strip).
    TipThe gas system need not be taken apart at every field strip; the manual calls for it every 5,000 rounds or when there is water, debris or excessive fouling in the gas system.
  2. Using the bolt handle, unscrew the gas cylinder plugs counterclockwise as viewed from the front of the barrel.
    Removed at this step: Gas cylinder plugs (2)
  3. Remove the gas pistons from the front end of the gas cylinders.
    Removed at this step: Gas pistons (2)

Install the magazine follower, spring and spring seal ring

Detail Reassembly

Puts the follower in red end first, then the spring, then squeezes and rolls the magazine spring seal ring into the tube mouth (operator reassembly step 7, p. 48). Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator reassembly, step 7, p. 48 archive.org [5]

  1. Insert the magazine follower into the end of the magazine tube with its red, smaller-diameter end with the raised tactile ring going in first.
  2. Insert the magazine spring into the magazine tube behind the follower.
  3. Insert the magazine spring seal ring, squeezing it and pressing down from the top while rotating it forward until the seal is set.
    WarningMake sure the muzzle end of the magazine points in a safe direction while removing the magazine cap and the magazine spring seal ring. The magazine parts are under considerable spring tension and can injure you or bystanders if released. If the magazine spring seal is worn, it may come out when the cap is removed and eject the magazine spring.
    TipFigure 42 shows the three stages of seating the seal ring.
  4. Install the barrel and forearm, then screw the magazine cap on hand tight to the last click.
    TipThe manual's step 8 holds the bolt group at least 1/4 in to the rear with the bolt handle while the barrel extension goes in, and checks that both gas pistons enter their holes in the front of the receiver.

Install the pistol grip and telescoping buttstock

Detail Reassembly

Screws the pistol grip onto the receiver until flush and vertical, then fits the telescoping buttstock to the recoil tube by the reverse rotation sequence (p. 44). The trigger group goes back in afterwards. Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Applies to: M1014 / M4 with the telescoping buttstock and detachable pistol grip

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator reassembly, Weapon, Buttstock, archive.org [5]

  1. Place the pistol grip over the rear end of the recoil spring tube at the back of the receiver.
  2. Screw the pistol grip onto the receiver clockwise, as viewed from the rear, until it is flush against the back of the receiver and vertical.
  3. Grip the telescoping buttstock with your firing hand and depress the button.
  4. Rotate the buttstock counterclockwise until its top lines up with the flat part of the recoil tube.
  5. Push the buttstock up the recoil tube to the inscribed line.
  6. Rotate the buttstock clockwise past vertical and push it forward.
  7. Rotate the buttstock counterclockwise and release the button.

Reassemble the bolt group

Detail Reassembly

Fits the bolt head with the extractor to the right, the cam pin with its index line parallel to the carrier, then the firing pin and spring, held in by the retaining pin pushed in from right to left (pp. 41-43). Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator reassembly, 2. Bolt group, pp. archive.org [5]

  1. Insert the bolt head into the front of the bolt carrier with the extractor to the right.
  2. Insert the cam pin through the hole in the bolt head so that the hole through the cam pin and the index line on its top run parallel with the bolt carrier.
  3. Place the firing pin spring onto the front end of the firing pin.
  4. Insert the firing pin, with its spring, into the hole in the back end of the bolt carrier.
  5. Press in on the back of the firing pin with your finger against spring tension and push the firing pin retaining pin into the bolt carrier from right to left.
    WarningDo not try to place the firing pin retaining pin completely behind the end of the firing pin.
  6. Check that the back end of the firing pin is visible at the back of the bolt carrier and that the firing pin moves freely when pushed in with a pointed object.

Install the gas pistons and gas cylinder plugs

Detail Reassembly

Puts the gas pistons back with the long extension toward the rear of the barrel and tightens the plugs clockwise with the bolt handle (Operator reassembly, 1. Barrel, p. 41). Operator level in the USMC operator's manual, which states that only a trained armorer may go beyond this level of disassembly.

Follows TM 10698A-10/1 (preliminary): Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147) [For Official Use Only] — Headquarters, U.S. Marine Corps (Marine Corps Systems Command), p. Operator reassembly, 1. Barrel, p. 41 archive.org [5]

  1. Install the gas pistons in the gas cylinders with the long extension facing the rear of the barrel.
  2. Install the gas cylinder plugs and tighten them clockwise, as viewed from the front of the barrel, using the bolt handle.

Reassembly

Reassembly
  1. Install the trigger group into the receiver and insert its pin fully.
  2. Slide the bolt assembly into the receiver, engaging the link with the recoil spring plunger.
  3. Install the bolt handle into the bolt.
  4. Reinstall the two gas pistons into their cylinders in the correct orientation.
    WarningReversed pistons will not seal and the shotgun will not cycle correctly.
  5. Set the barrel into the receiver with its extension seated fully and its ring over the magazine tube.
  6. Install the forend and thread the magazine cap on, hand-tightening firmly.
    WarningA loose magazine cap causes malfunctions and lets the barrel move. Check it before every use.
  7. Cycle the action several times and perform the function check.

Diagrams

public domain

These are reproduced from government technical manuals, which are not subject to copyright. Manufacturer manual diagrams are not reproduced here — the entry links to the manual instead.

Figures 25-27 — Removing the firing pin retaining pin; removing the firing pin and spring; removing the cam pin
Figures 25-27 — Removing the firing pin retaining pin; removing the firing pin and spring; removing the cam pin Line drawings of each bolt-group step, showing which side the retaining pin comes out and where the cam pin sits. TM 10698A-10/1 (preliminary) — Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147), p.39 — Headquarters, U.S. Marine Corps (Marine Corps Systems Command). Source. Public domain (US Government work).
Figures 21-22 — Rotating and removing the telescoping buttstock module
Figures 21-22 — Rotating and removing the telescoping buttstock module Shows the button, the rotation directions and the slide-off path for the telescoping buttstock. TM 10698A-10/1 (preliminary) — Preliminary TM 10698A-10/1, U.S. Marine Corps Technical Manual: Operator's Manual for Shotgun, Combat, 12 Gauge, Semi-Automatic, M1014 (1005-01-472-3147), p.37 — Headquarters, U.S. Marine Corps (Marine Corps Systems Command). Source. Public domain (US Government work).

Torque specifications

No sourced torque values from the manufacturer are recorded for this firearm. Where a fastener has a specified torque — action screws, scope bases, muzzle devices, barrel nuts — get it from the manufacturer or a gunsmith rather than estimating it.

What the manufacturer does say: The manufacturer's documents give no torque value. They say: "Screw on the fore-end fastening cap, on the end of the tubular magazine and tighten firmly until the barrel and the fore grip are locked perfectly against the receiver (fig. 10)." (M4 Tactical Shotgun Product Manual, PDF p. 49)

Reported by other sources — not the manufacturer

Not a manufacturer specificationThese values come from the people and publications named beside each one, not from Benelli Armi. They are recorded with who said them and their exact words so you can judge them — not as a recommendation. Confirm any of them with the manufacturer or a licensed gunsmith before you put a wrench on your firearm; a wrong value can crack a stock, strip a thread or loosen a muzzle device.
FastenerTorqueWho says so, and their wordsWhere it comes from
Handguard mounting bolts (6: four on forward ring, two on rear retaining cap)
Midwest Industries Benelli M4 M-LOK Handguard (MI-BENM4-HG) on a Benelli M4 (and clones)		 20 in-lb
2.3 N·m · 1.7 ft-lb

Reported by Midwest Industries, Inc.
Secondary — a parts or tool maker, or a gunsmithing publisher

Start screws finger tight; tighten barrel assembly fully seated; then torque all 6; then brass set screws only until they touch.

“Tighten all 6 mounting bolts to 20inch lbs.”

 Midwest Industries Benelli M4 Handguard (MI-BENM4-HG) — Instructions — Midwest Industries, Inc., PDF p. 1 (single page) midwestindustriesinc.com [6]
Reflex sight mount to receiver (three screws and washers, factory rail holes)
Mesa Tactical RMR-footprint reflex sight mount on a Benelli M4		 approx. 15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Mesa Tactical
Secondary — a parts or tool maker, or a gunsmithing publisher

Threadlocker: Purple or blue thread locker recommended

“For Benelli M2 Tactical and Benelli M4 use the three screws and washers. For Beretta 1301 Tactical use the two metric flathead screws. Tighten to about 15 inch-lbs.”

 Mesa Tactical Reflex Sight Mounts Manual (46020 rev e) — Mesa Tactical, PDF p. 4 of 8 mesatactical.com [7]
ACRO sight mount to receiver (#8-40 x 1/4" flathead screws, three)
Mesa Tactical ACRO-footprint reflex sight mount on a Benelli M4		 approx. 15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Mesa Tactical
Secondary — a parts or tool maker, or a gunsmithing publisher

Threadlocker: Purple or blue thread locker recommended

“Use three screws and included hex key to tighten the sight mount to the receiver. Tighten to about 15 inch-lbs.”

 Mesa Tactical Reflex Sight Mounts Manual (46020 rev e) — Mesa Tactical, PDF p. 6 of 8 mesatactical.com [7]
SureShell carrier/ACRO mount to receiver (four #8-40 screws)
Mesa Tactical SureShell carrier with ACRO sight mount on a Benelli M4		 approx. 15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Mesa Tactical
Secondary — a parts or tool maker, or a gunsmithing publisher

Threadlocker: Purple or blue thread lock recommended

“Use the four screws and hex key included in your zip bag hardware kit. Tighten screws to about 15 inch-lbs.”

 Mesa Tactical SureShell Carrier and ACRO Sight Mount Manual (46028) — Mesa Tactical, PDF p. 5 of 9 mesatactical.com [8]
Integrated-rail SureShell carrier to receiver (four or five screws and washers, factory rail holes)
Mesa Tactical Integrated Rail SureShell shotshell carrier on a Benelli M4/M1014		 approx. 15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Mesa Tactical
Secondary — a parts or tool maker, or a gunsmithing publisher

Threadlocker: Blue Loctite on each screw

“the four or five screws and washers (the SureShell carriers for the Benelli SuperNova Tactical do not include washers). Tighten to about 15 inch-lbs and use a drop of blue Loctite® on each screw.”

 Mesa Tactical SureShell Shotshell Carriers — Assembly and Operation Guide (47374) — Mesa Tactical, PDF p. 16 of 20 mesatactical.com [9]

Materials and factory finish

As stated by Benelli Armi. Prep, masking and cure depend on these; a polymer or aluminium part, a nitrided or anodised finish, and a blued steel part are each a different job. Variants with other finishes may exist — check the maker's page for the exact SKU on the bench.

ComponentMaterialFactory finishWhere it comes from
Receiver
M4 Black		Ergalmat black anodisedBenelli M4 Black — technical data — Benelli Armi S.p.A. benelli.it [4]
“RECEIVER FINISHING Ergal, mat black anodised, anti-glare”
Stock
M4 Black		Technopolymer—Benelli M4 Black — technical data — Benelli Armi S.p.A. benelli.it [4]
“STOCK AND FORE-END Technopolymer”
Barrel
M4 Black		—phosphatedBenelli M4 Black — technical data — Benelli Armi S.p.A. benelli.it [4]
“The barrel is chromed inside and phosphated outside.”

Function check

After every reassemblyPerform these checks on a verified-unloaded firearm. If any check fails, the firearm is not safe to fire — stop and see a licensed gunsmith.

Maintenance

Lubrication points

Cleaning notes

Gas-operated shotguns foul their gas system quickly. Clean the gas ports in the barrel, the piston, the piston seals, and the magazine tube every few hundred rounds. Do not oil the gas piston area heavily — oil there mixes with carbon into a paste that stops the gun.

Suggested inspection interval: roughly every 500 rounds. This is a general guideline, not a manufacturer specification.

Wear parts to inspect

Gas piston and seals · Barrel seal O-ring where fitted · Action spring · Extractor · Link

Common issues

SymptomLikely causeWhat to do
Short-stroking or failure to lock backCarbon buildup in the gas cylinders and on the pistonsClean the gas pistons and cylinders thoroughly. This is the standard M4 maintenance item.
Shotgun will not cycle after cleaningGas pistons installed reversedCheck piston orientation against a parts diagram.
Malfunctions that come and goLoose magazine capHand-tighten firmly and check before use.

Also covers

The procedures above are reported to apply to: Benelli M1014 · Benelli M4 Tactical and H2O variants. Verify against the manual for your specific model.

Similar manual of arms

Legal notes

Not legal adviceBarrel length and overall length determine legal classification. Collapsible-stock M4 variants have been subject to import and configuration restrictions in some jurisdictions.

Sourcing

Confidence
medium — Drawn from reliable secondary sources and consistent across references, but not confirmed against a primary source.
Verification
Community reviewed only
Last updated
2026-10-29

References

Every source this page draws on, with its web address so you can read it yourself. Numbers in brackets elsewhere on the page point here.

Notes: The M4 is the gas-operated outlier in a line otherwise built on the inertia system. That distinction drives its entire maintenance profile and is the thing most likely to catch out someone who owns other Benellis.

Found something wrong? Corrections are the most valuable contribution to this project. Open an issue with the model, the step, and a source.