Silencerco AC863 Threaded Barrel for Glock 21 - .578x28 Thread Pitch

The SilencerCo AC863 threaded barrel for Glock 21 is built from 416R stainless steel and ready to accept a quality suppressor. This barrel replaces your factory tube with a professionally threaded option, featuring a .578x28 thread pitch that's the standard for .45 ACP suppressors. At 5.2 inches long, it maintains the handling characteristics of your Glock 21 while giving you the flexibility to run suppressors for subsonic shooting, reduced signature, or just a quieter trip to the range. SilencerCo offers this barrel in a black nitride finish for corrosion resistance and durability in the field, or natural stainless if you prefer the classic look. It ships with a thread protector to keep the muzzle threads clean and protected when you're running it unsuppressed.

Threading your Glock is straightforward—barrel swaps on these pistols are user-serviceable without gunsmithing. Once installed, you've got a ready platform for suppressors, and the threads are properly cut to spec so fitment is reliable. Whether you're a hunter looking to reduce hearing fatigue, a shooter who values neighbors, or just someone who appreciates the versatility a threaded barrel brings, this is a solid upgrade that doesn't compromise the gun's ergonomics or reliability.

The 416R stainless construction is proven material in firearms manufacturing—it resists corrosion, handles higher pressures, and polishes to a fine finish. The nitride coating adds a protective layer that's tough enough for hard use. If you're running a suppressor on a .45 ACP pistol, having the right barrel match—both in thread pitch and length—matters for sound signature and reliability.

Key Features

• 416R stainless steel construction for durability and reliability
• .578x28 thread pitch—the standard for .45 ACP suppressors
• 5.2-inch barrel length, true to Glock 21 proportions
• Black nitride finish resists corrosion and wear
• Includes thread protector to keep muzzle threads clean
• User-serviceable installation—no gunsmithing required

Specifications

Frequently Asked Questions

Will this threaded barrel work with my .45 ACP suppressor?

Yes—the .578x28 thread pitch is the industry standard for .45 ACP suppressors. Any suppressor threaded to that spec will fit this barrel.

Is installation something I can do myself?

Yes. Glock barrel swaps are user-serviceable. The barrel simply lifts out after you lock the slide back and remove the recoil spring assembly. No gunsmithing or special tools required.

What finish options are available?

This barrel ships in black nitride. SilencerCo also produces their threaded barrels in natural stainless steel finish, though you'll want to verify availability for the .45 ACP model.

Does it come with a suppressor?

No. The barrel includes a thread protector to keep the muzzle threads clean. You'll need to source your own suppressor separately.