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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Glock 42

field strip ~1 min · reassembly ~1 min · detail strip ~20 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.
Glock Ges.m.b.H. limits owner disassembly The maker's own procedure goes as far as: Field strip only: slide, recoil spring assembly, barrel and frame.. GLOCK tells owners never to disassemble the pistol beyond the field strip; any further disassembly must be done by a GLOCK-Certified Armorer, and otherwise voids the warranty. (GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H., p. 24 eu-assets.contentstack.com [1])

Specifications

Manufacturer
Glock Ges.m.b.H.
Origin
Austria
Category
Pistol
Action
Striker-fired, short recoil
Calibers
.380 ACP
Capacity
6+1 with the standard magazine
Production
2014–present (in-production)

Model-specific safety

Trigger press required to disassemble This design requires pressing the trigger as part of the takedown. That makes verifying an empty chamber non-negotiable. Check it twice, keep the muzzle in a safe direction, and never take a shortcut on this step.

Under spring tension

Easily lost parts

Slide lock spring (detail strip only) · Firing pin safety and spring (detail strip only)

Tools

No tools required for the field strip.

Shop difficulty

Shop tier 1 Tier 1 — easy among pistols, for the full job: strip to the parts that get coated and put it back together working. About 35 line items in GLOCK's slimline (G42) list including the magazine; two frame pins, punch-only work. Minor traps only: the slide cover plate and holding the slide stop lever while the trigger pin goes in. Same design family as the Glock 19 (the reference Tier 1 pistol).

Parts: 35 numbered parts (Complete pistol incl. magazine; the parts list on this page = GLOCK's p. 50 list with the 'Exploded drawing GLOCK 42' (p. 51); 35 pieces), from GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H., p. 50 eu-assets.contentstack.com [1].

Bench time: about 15 min to strip, 20 min to rebuild (estimate). 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. Two frame pins;

Small parts: 6 pins, 7 springs, 2 detents or plungers (counted from the manufacturer's parts list (one per key number unless a quantity is given))

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. Press the magazine release, remove the magazine, and set it away from the work area.
    Removed at this step: Magazine
  3. Retract the slide fully to eject any chambered round and lock it open on the slide stop lever.
  4. Visually inspect the chamber and magazine well, then physically feel the chamber to confirm it is empty.
    WarningBoth checks, every time. The next procedure requires pressing the trigger.
  5. Remove all live ammunition from the work surface.

Field Strip

Field Strip

The factory manual's sequence. Four parts, no tools, and identical across the Glock line.

  1. Complete the Clear and Make Safe procedure, and put on safety glasses.
    WarningThe manual requires safety glasses when disassembling — components are under spring pressure.
  2. Release the slide to the forward position, either by pressing the slide stop lever down or by pulling the slide fully back and releasing it.
  3. With the muzzle pointed in a safe direction, pull the trigger. The trigger must be in its rearmost position for the slide to come off.
    WarningVerify the chamber is empty before this step. If the trigger is in the forward position, the pistol may be loaded.
  4. Hold the pistol with your firing hand, fingers across the top of the rear of the slide in front of the rear sight and thumb on the rear of the frame.
  5. Using your fingers, retract the slide about 1/8 in (3 mm) and hold it there.
    TipPull it too far and the trigger resets to the forward position. If that happens, pull the trigger again with the muzzle in a safe direction and start over.
  6. Using the thumb and index finger of your non-firing hand, pull the slide lock down evenly on both sides.
  7. While holding the slide lock down, push the slide forward and off the frame.
    Removed at this step: Slide assembly
  8. Press the recoil spring assembly toward the front (muzzle end) of the slide while pulling it up to remove it.
    WarningIt is under spring tension. Keep control of it.
    Removed at this step: Recoil spring assembly
  9. Holding the barrel by the barrel locking cams, lift it and push it toward the front of the slide, then pull it up and toward the rear to remove it.
    TipForward first, then up and rearward. It does not simply lift out.
    Removed at this step: Barrel
  10. Stop here for routine cleaning. The frame and slide internals do not need to come apart for normal maintenance.

Reassembly

Reassembly
  1. Hold the slide upside down, insert the barrel, and seat it fully by its locking cams.
  2. Insert one end of the recoil spring assembly into the slide and press the other end toward the front of the slide to compress the spring, pushing down until the large end rests in the second, semi-circular notch on the barrel locking cams.
    TipThe second semi-circular notch on the locking cams is the seat. If the assembly keeps popping out, it is not in that notch.
  3. Holding the frame in your firing hand with your finger off the trigger and outside the trigger guard, place the slide on top of the frame in front of the slide rails.
  4. Push the slide toward the back of the frame until the slide lock snaps up and locks the slide into place.
    WarningDo not hold the slide lock down during reassembly. It snaps up on its own.
  5. Release the slide and let it run forward into battery, then perform the function check.

Patent drawings

not under copyright

Drawings from US patents on this design. A patent shows the invention as the inventor filed it; the firearm that shipped can differ in detail, and later production often does. Use them to see how the parts relate, not as a parts reference or a procedure. Per the USPTO, the text and drawings of a patent are typically not subject to copyright; each patent here was checked for a copyright notice.

US Patent 9,316,455 — Spring for a trigger slide of a pistol

Reinhold Hirschheiter · assigned to Glock Technology GmbH · filed 2014-12-11 · granted 2016-04-19. Full patent (USPTO)

The compression trigger spring on a guide pin with a hook that acts on the trigger bar (trigger slide) inside the Glock trigger mechanism housing.

Why this is the Glock 42’s patent: listed on the maker’s patent-marking page — Virtual Patent Marking of GLOCK® Products (Version 1, Released: August, 2026) — GLOCK (linked as 'Patents' from the us.glock.com site footer), p. 1, row G42, column US9316455B2 eu-assets.contentstack.com [7]: “The following GLOCK® Products, the according models and product generations, and components thereof may be protected by one or more of the following Patents and Designs. … G42 … US9316455B2”

US Patent 9,316,455, Sheet 2 of 4 — Fig. 4, Fig. 5
US Patent 9,316,455, Sheet 2 of 4 — Fig. 4, Fig. 5 The patent: “FIG. 4 shows a pistol in side view, partially in section, in a state ready for firing, FIG. 5 shows the detail V from FIG. 4,” Drawn for the patent, as filed; the production firearm may differ in detail. US Patent 9,316,455 — Spring for a trigger slide of a pistol, Sheet 2 of 4 — United States Patent and Trademark Office. Source. US patent drawing, not subject to copyright.
US Patent 9,316,455, Sheet 4 of 4 — Fig. 7, Fig. 8, Fig. 9
US Patent 9,316,455, Sheet 4 of 4 — Fig. 7, Fig. 8, Fig. 9 The patent: “FIG. 7 shows the detail VII from FIG. 6, FIG. 8 shows the spring according to the invention together with hook part in side view, and FIG. 9 shows the spring from FIG. 8 in a perspective view.” Drawn for the patent, as filed; the production firearm may differ in detail. US Patent 9,316,455 — Spring for a trigger slide of a pistol, Sheet 4 of 4 — United States Patent and Trademark Office. Source. US patent drawing, not subject to copyright.

US Patent 9,933,222 — Catch device for the breech of a pistol

Reinhold Hirschheiter · assigned to Glock Technology GmbH · filed 2014-12-11 · granted 2018-04-03. Full patent (USPTO)

The slide stop lever (catch device for the breech) and its compression spring seated in a slot of the frame, pivoting on the trigger pin.

Why this is the Glock 42’s patent: listed on the maker’s patent-marking page — Virtual Patent Marking of GLOCK® Products (Version 1, Released: August, 2026) — GLOCK (linked as 'Patents' from the us.glock.com site footer), p. 1, row G42, column US9933222B2 eu-assets.contentstack.com [7]: “The following GLOCK® Products, the according models and product generations, and components thereof may be protected by one or more of the following Patents and Designs. … G42 … US9933222B2”

US Patent 9,933,222, Sheet 2 of 4 — Fig. 4
US Patent 9,933,222, Sheet 2 of 4 — Fig. 4 The patent: “FIG. 4 shows a catch device according to the invention in a view similar to FIG. 1, partially in section,” Drawn for the patent, as filed; the production firearm may differ in detail. US Patent 9,933,222 — Catch device for the breech of a pistol, Sheet 2 of 4 — United States Patent and Trademark Office. Source. US patent drawing, not subject to copyright.
US Patent 9,933,222, Sheet 4 of 4 — Fig. 8, Fig. 9, Fig. 10
US Patent 9,933,222, Sheet 4 of 4 — Fig. 8, Fig. 9, Fig. 10 The patent: “FIG. 8 shows an illustration according to FIG. 4 in an active catch position, FIG. 9 shows the detail IX from FIG. 5, but in the position of FIG. 8, and FIG. 10 shows the section X-X from FIG. 9.” Drawn for the patent, as filed; the production firearm may differ in detail. US Patent 9,933,222 — Catch device for the breech of a pistol, Sheet 4 of 4 — United States Patent and Trademark Office. Source. US patent drawing, not subject to copyright.

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: "Never further disassemble your GLOCK pistol (Picture 27). Any further disassembly must be performed by a GLOCK-Certified Armorer." (GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use), p. 24) "The front sights can be easily installed by a GLOCK-Certified Armorer." (GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use), p. 43)

Reported by other sources — not the manufacturer

Not a manufacturer specificationThese values come from the people and publications named beside each one, not from Glock Ges.m.b.H.. 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
Front sight screw
GLOCK pistols; Night Fision front sight with the Night Fision screw
5–7 in-lb
0.56–0.79 N·m · 0.42–0.58 ft-lb

Reported by Night Fision (sight maker) support knowledge base
Secondary — a parts or tool maker, or a gunsmithing publisher

Threadlocker: "de-grease and apply high strength thread locker to the front sight screw when installing" (Night Fision screws come with thread locker pre-applied per its install guide)

“The recommendation for a Glock front sight screw is to use 5-7 in/lbs. (0.565-0.791 N-m) of torque.”

What is the Glock Front Sight Screw Torque Spec? — Night Fision (sight maker) support knowledge base nightfisionorg.freshdesk.com [3]
Front sight screw
GLOCK pistols; Night Fision front sight with the Night Fision screw
max. 10 in-lb
1.1 N·m · 0.83 ft-lb

Reported by Night Fision (sight maker) support knowledge base
Secondary — a parts or tool maker, or a gunsmithing publisher

“DO NOT EXCEED 10in/lbs. (1.13 N-m) of torque or risk of failure is very high.”

What is the Glock Front Sight Screw Torque Spec? — Night Fision (sight maker) support knowledge base nightfisionorg.freshdesk.com [3]
Front sight screw
GLOCK pistols; AmeriGlo front sight with AmeriGlo screw
10 in-lb
1.1 N·m · 0.83 ft-lb

Reported by AmeriGlo (sight maker)
Secondary — a parts or tool maker, or a gunsmithing publisher

Hold the front blade square and firmly during final tightening; the screw must stay seated squarely in the head (sight most likely to rotate off-center then).

Threadlocker: "a very small drop of Loctite on the end threads of the screw"

“The screw should be tightened snugly (wrist-tight, 10 in-lbs) against the bottom of the slide.”

Sight Installation Instructions — AmeriGlo (sight maker) ameriglo.com [4]
Red-dot optic mounting screws (6-32 flat head, supplied) into EGW rear-dovetail sight mount
Glock 42 (non-MOS slide only; EGW: 'Does not fit ANY/ALL Glock MOS models'); EGW notes the RMR mount is wider than this slide but still works with the EGW 'Trijicon RMR / SRO, Holosun 407c / 507c Sigh
15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Evolution Gun Works (EGW)
Secondary — a parts or tool maker, or a gunsmithing publisher

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)

“Torque mounting screws to 15in/lbs”

Trijicon RMR / SRO, Holosun 407c / 507c Sight Mount for Glock (EGW product page, installation instructions section) — Evolution Gun Works (EGW) egwguns.com [5]
Red-dot optic mounting screws (supplied) into EGW rear-dovetail sight mount (Docter/Venom/Viper/FastFire footprint)
Glock 42 (non-MOS slide only; EGW: 'Does not fit ANY/ALL Glock MOS models'); EGW notes the RMR mount is wider than this slide but still works with the EGW 'Glock Red Dot Mount | Fits Vortex Venom, Vip
15 in-lb
1.7 N·m · 1.2 ft-lb

Reported by Evolution Gun Works (EGW)
Secondary — a parts or tool maker, or a gunsmithing publisher

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)

“Torque mounting screws to 15 in/lbs”

Glock Red Dot Mount | Fits Vortex Venom, Viper & Burris FastFire | EGW (EGW product page, installation instructions section) — Evolution Gun Works (EGW) egwguns.com [6]

Materials and factory finish

As stated by Glock Ges.m.b.H.. 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
Frame
G42
polymer—GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H. eu-assets.contentstack.com [1]
“FRAME: The frame (17) is made of polymer with hardened steel guides.”
Slide
G42
—matte blackGLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H. eu-assets.contentstack.com [1]
“SLIDE: The advanced surface treatment of the slide (1) results in optimal hardness by considerably reducing wear and tear and it makes it corrosion resistant, even when operating in saltwater conditions. The matte black surface minimizes light reflection – an advantage in tactical circumstances.”
Sights
standard front sights (steel sights optional)
polymer—GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H. eu-assets.contentstack.com [1]
“All GLOCK pistol models come standard with polymer front sights (16a), which provide excellent damping characteristics on impact. Steel front sights with a white contrast point, steel luminescent sights and steel night sights with a self-illuminating tritium contrast point are available as options.”

Parts list

Transcribed from the manufacturer's parts list (GLOCK Owner's Manual — Models G17 to G48 (Instructions for Use) — GLOCK Ges.m.b.H., p. 50 eu-assets.contentstack.com [1]) — G42: list on p. 50, paired with "Exploded drawing GLOCK 42" (p. 51). Omitted: the manual's other lists, p. 46 (G17 Gen4 drawing) and p. 48 (G17 Gen5 drawing).. Key numbers refer to the exploded view in that document.

35 parts
KeyPartPart no.QtyGroup
1Slide1
2Barrel1
3Recoil spring assembly
The recoil spring assembly is designed to be used as a one-piece unit for easier handling and must not be disassembled. Prior to 1991, GLOCK pistols were supplied with a separate recoil spring and recoil spring tube.
1
4Firing pin1
5Spacer sleeve1
6Firing pin spring1
7Spring cups1
8Firing pin safety1
9Firing pin safety spring1
10Extractor1
11Extractor depressor plunger1
12Extractor depressor plunger spring1
13Spring-loaded bearing1
14Slide cover plate1
15Rear sight1
16aFront sight1
16bFront sight screw1
17Frame1
18Magazine catch spring1
19Magazine catch1
20Slide lock spring1
21Slide lock1
22Locking block1
23Trigger mechanism housing with ejector1
24Connector1
25Trigger spring1
26Trigger with trigger bar1
27Slide stop lever1
28Trigger pin1
29Trigger housing pin (short)1
31Magazine tube1
32Follower1
33Magazine spring1
34Magazine insert1
35Magazine floor plate1

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

Glock specifies a very light application of lubricant — roughly one drop per point. Over-lubrication attracts carbon. Keep the striker channel dry and free of solvent.

Suggested inspection interval: roughly every 5000 rounds. This is a general guideline, not a manufacturer specification.

Wear parts to inspect

Recoil spring assembly · Extractor · Slide lock spring · Magazine springs and followers · Trigger spring

Common issues

SymptomLikely causeWhat to do
Slide will not come off after pulling the slide lock downTrigger not pressed after the last rack, or the slide retracted too farReturn the slide to battery, verify the chamber is empty, press the trigger, then retract only about 1/8 in.
Recoil spring assembly falls out during reassemblyAssembly resting on the barrel rather than seated in the barrel lug cutReseat it in the half-moon cut on the underside of the barrel lug.
Erratic ejection or brass to the faceWorn recoil spring assembly, extractor, or ejectorReplace the recoil spring assembly first as the cheapest variable, then inspect the extractor and ejector. see a gunsmith

Similar manual of arms

Legal notes

Not legal adviceSome jurisdictions regulate magazine capacity. Modifying the connector, striker, or firing pin safety changes trigger characteristics and, done wrong, produces an unsafe pistol.

Sourcing

Confidence
high — Cross-checked against a primary source such as the manufacturer's manual or an issuing military technical manual.
Verification
Checked against the manufacturer manual
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: Verified against the factory manual on 2026-09-14. The procedure as previously written was confirmed correct, including the 1/8 in (3 mm) slide retraction. Detail added from the manual: the reason over-retracting fails is that it resets the trigger forward; the barrel comes out by pushing it toward the front of the slide and then up and rearward; the recoil spring assembly seats in the second semi-circular notch on the barrel locking cams; and safety glasses are required. Field strip and reassembly are identical across the Glock line and unchanged between generations; only internal parts differ. The smallest Glock. Slimline parts are specific to this model. The very short slide means the takedown retraction distance is smaller still — a firm grip matters.

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