AR-15 – Compensator Muzzle Brake – 5.56 1/2x28 – Apollo S
PLEASE DOUBLE CHECK DETAILS AND FITMENT BEFORE PURCHASE.
The Ultradyne USA Apollo S is a performance-focused compensator muzzle brake for AR-15 pattern rifles chambered in .223 Remington and 5.56 NATO with 1/2x28 muzzle threads. It uses 416 stainless steel construction, a black nitride finish, and an included shrouded timing nut for proper installation and indexing.
Fitment
Fits many AR-15 pattern rifles chambered in .223 Remington or 5.56 NATO with 1/2x28 muzzle threads and at least 0.600 inch of barrel thread length.
Does NOT fit
Does not fit barrels with non-1/2x28 thread pitch, insufficient thread length, barrels shorter than the manufacturer minimum, or setups with clearance issues. Verify caliber, thread pitch, barrel length, and handguard clearance before purchase.
What it does
The Apollo S is designed to reduce recoil and muzzle rise through multi-port gas redirection, helping shooters keep the gun flatter during faster strings and follow-up shots.
Why it’s worth it
This is a purpose-built rifle compensator with real competition pedigree, proper materials, and included timing hardware. For customers chasing flatter shooting on a 5.56 build, it is a serious upgrade instead of random muzzle junk off the bargain pile.
Specs
• Caliber: .223 Remington / 5.56 NATO
• Thread pitch: 1/2-28 UNEF-2B
• Minimum barrel length: 14 in
• Minimum barrel thread length: 0.600 in
• Material: 416 stainless steel
• Finish: Salt bath nitride / black nitride
• Mounting: Shrouded timing nut
• Length: 2.94 in
• Outside diameter: 0.975 in
• Weight: 4.4 oz brake only
• Total weight: 5.2 oz with timing nut
• Wrench flats: 13/16 in
• Timing nut wrench flats: 13/16 in
What’s included
• Ultradyne Apollo S compensator muzzle brake
• Shrouded timing nut
Tools needed
Use an appropriate upper or barrel fixture, vise setup, and the correct wrench size for installation.
Install notes
Proper timing and alignment matter. Confirm thread engagement, bore clearance, and shoulder fit before live fire. Perform full function testing after installation.
Verify before you buy
Verify your rifle is chambered in .223 Remington or 5.56 NATO, uses 1/2x28 muzzle threads, has a barrel at least 14 inches long, and has enough clearance for a 0.975 inch outside diameter muzzle device.
⚠ Trademark & Compatibility Disclaimer
IronKells Armory LLC is not affiliated with, endorsed by, or sponsored by any manufacturer mentioned. All trademarks are the property of their respective owners and are used only to identify compatibility or fitment.
⚠ Install & Compatibility Disclaimer
Installation should be performed by a qualified armorer or gunsmith. Improper installation, modification, or use may affect firearm safety and reliability. Buyer is responsible for verifying compatibility, performing proper function testing, and ensuring safe operation.
