Glock wear parts: what to replace at 5k, 10k and 20k rounds

A Glock will run a very long time without attention, which is exactly why parts get replaced late. Springs weaken quietly, extractors chip a little at a time, and the first sign is a failure at the worst moment. This is a maintenance schedule by round count, with the symptoms of each worn part and a spares kit that covers most of it. Round counts are typical for 9mm with factory ammunition; +P, .40 S&W and 10mm shorten them, and a pistol carried but rarely fired follows the calendar instead.

Every range trip

Field strip, wipe the slide rails, barrel and breech face, run a dry patch through the striker channel if it is out, oil the rails and barrel lightly and inspect the extractor claw and the recoil spring for damage. Check that the slide lock spring holds the lock up and that the magazines drop free. Five minutes.

Every 3,000 to 5,000 rounds: the recoil spring assembly

The recoil spring is the fastest-wearing part in the pistol. Glock's armorer guidance and most instructors put the dual assemblies on Gen 4 and Gen 5 at around 5,000 rounds and the Gen 3 single spring at around 3,000, less with +P. Symptoms of a tired spring: brass landing farther and farther back, failures to return to battery, a slide that feels loose when racked. Replace on schedule; it costs little and the failure mode is the pistol not firing the second shot.

Every 5,000 rounds: springs and a look inside

Magazine springs on range magazines, or when the last round nose-dives or the slide stops locking back.
Trigger spring: inspect the hooks; replace at any sign of wear. It breaks without warning.
Slide lock spring: the Gen 3 and Gen 4 leaf fatigues; replace it here and keep a spare.
Extractor and depressor plunger: inspect the claw for chips and the bearing for wear; replace the plunger assembly if ejection has become erratic.
Striker spring: inspect; replace if primers show lighter dents than they used to.

Every 10,000 rounds: the slide internals

Replace the striker spring, cups and the firing pin safety spring as a set; they are cheap and the striker spring has done its work. Replace the extractor depressor plunger assembly. Inspect the striker tip for wear and the extractor claw closely; replace the extractor if it shows any chipping. Replace the recoil spring assembly again. Inspect the slide stop lever tip and the magazine catch for wear, and the frame pins for looseness.

Every 20,000 rounds: the frame parts

Replace the extractor regardless of appearance, the slide stop lever if the slide has been slow to lock back, and the magazine catch spring. Inspect the locking block cam face for peening and the trigger bar's cruciform for rounding; replace either if worn. Inspect the frame rails and the area around the pins for cracks. Consider a new trigger housing if the cruciform shelf shows wear, which appears as a pull that breaks earlier than it used to. A Glock at 20,000 rounds with these parts replaced is functionally new.

Beyond 20,000

Repeat the cycle. Barrels last well past 50,000 rounds in 9mm; slides and frames last indefinitely short of a crack. The parts that fail late are the locking block, the slide stop and, rarely, a rail. A pistol shot that much has usually earned a second recoil assembly, a third set of springs and a new extractor, and nothing else.

Ammunition and the schedule

Hot ammunition moves the schedule up. A steady diet of +P in a 9mm, or full-power loads in a 10mm, roughly halves the recoil spring interval and wears the extractor and locking block faster; a diet of light target loads stretches it. Dirty or steel-cased ammunition fouls the extractor and chamber faster than brass. If you shoot the hot stuff, treat the 5,000 round interval as 3,000 and inspect the extractor every trip. If you shoot mild loads and clean regularly, the schedule above is conservative.

By the calendar

A carry pistol fired 200 rounds a year wears its springs from cycling less than it ages them from storage, and springs age slowly; replace the recoil, striker and trigger springs every five years, the magazine springs on carried magazines every three to five, and the tritium sights when they dim, around ten to twelve years. Fire the carry ammunition once a year and replace it.

Symptoms to parts

Brass far behind you, slide not returning fully: recoil spring.
Last round fails to feed, no lock-back: magazine spring or follower.
Trigger does not return: trigger spring.
Slide comes off in the hand: slide lock spring.
Light strikes: striker spring or a dirty channel.
Erratic ejection: depressor plunger assembly, then extractor, then ejector.
Slide hesitates into battery: recoil spring, then locking block.

The spares kit

A recoil spring assembly for your generation, a trigger spring, a slide lock spring, a striker spring with cups, a firing pin safety spring, an extractor depressor plunger assembly with the right bearing, magazine springs and a follower, and a set of the three frame pins. It fits in a sandwich bag, costs less than a box of premium ammunition and fixes nearly every failure a Glock can have. The parts are named in slide parts and frame parts, and the barrel's own care in Glock barrels. Browse Glock springs and wear parts; they ship to your door.

General information, not legal advice. Current as of September 2026. Laws change; check the official source before you act.