PSA Gen4 9mm Bolt Carrier Group (Nitride)

Nitride-treated 8620 steel Gen4 9mm BCG for PSA Glock-pattern platforms.

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Quick Specs

Price: $150
Weight: N/A
Brand: Palmetto State Armory
Category: bcg

Features

•PSA Gen4 9mm bolt carrier group
•Nitride-treated 8620 steel bolt
•Enhanced firing pin
•External 5.56-style extractor
•Glock-pattern platform

Capability Boosts

Reliability+1

Recommended For

Home Defense

Duty/Patrol

duty

Outdoor Defense

first pistol

new shooters

+11 more

Compatibility Tags

family: pccfamily: ar-patternplatform: custom-ar-9caliber: 9mmar9-system: simple-blowbackmag-type: glock

Overview

The PSA Gen4 9mm Bolt Carrier Group uses a nitride-treated 8620 steel bolt, an enhanced firing pin, and an external 5.56-style extractor. PSA states that it is compatible with most aftermarket fire control groups. It is the standard BCG in PSA Gen4 9mm uppers, pistols, and carbines, which use Glock-pattern magazines.

In an August 2026 bench test, the Palmetto State Armory G4 bolt ran the Partisan Disruptor and Triggered Company LAT cassette FRTs without weight modification. That result applies to cassette systems only. Selector-style forced reset systems still require the internal weight to be notched or a pre-cut carrier.

Key Features

PSA Gen4 9mm bolt carrier group
Nitride-treated 8620 steel bolt
Enhanced firing pin
External 5.56-style extractor
Compatible with most aftermarket fire control groups according to PSA
Standard BCG in PSA Gen4 9mm uppers, pistols, and carbines
Passed an August 2026 cassette FRT bench test without weight modification

Pros

+Uses an external 5.56-style extractor
+PSA states compatibility with most aftermarket fire control groups
+Ran two cassette FRT designs without weight modification in an August 2026 bench test

Cons

−PSA specifies compatibility with most aftermarket fire control groups rather than every group
−Selector-style forced reset systems still require a notched internal weight or a pre-cut carrier

Detailed Specifications

caliber: 9mm Luger
type: PSA Gen4 9mm bolt carrier group
boltMaterial: Nitride-treated 8620 steel
magazineCompatibility: Glock-pattern magazines
extractor: External 5.56-style extractor
firingPin: Enhanced
fireControlCompatibility: Most aftermarket fire control groups, according to PSA
manufacturer: Palmetto State Armory
sku: 5165449845