Make sure to always be aware of your surroundings when modifying your rifle.

Adjustments should only be done in safe areas. Check and double-check that the firearm is completely unloaded. Please be a responsible and mindful gun owner.

What you need:

  • Set of roll punches
  • Allen Wrench
  • Adjustable Gas Block
  • 15 to 20 Rounds


  1. Ensure the firearm is unloaded before separating the upper and lower receiver
  2. Firmly secure the upper receiver, and remove the handguard.
  3. Using an allen wrench (3/32” most likely), loosen the hex screws and remove the pre-installed gas block from the barrel.
  4. Dislodge the roll pin that’s holding the gas tube in place. Separate it from the gas block.
  5. Insert the gas tube into the adjustable gas block and make sure it is aligned (gas tube “mouth” facing down).
  6. Install the roll pin using the punch tool.
  7. Install your new adjustable gas block and gas tube on your rifle. Make sure that the gas port is (almost, if not) perfectly aligned over the gas port on the barrel and inside the gas block.
  8. Using the allen wrench, carefully tighten the bottom screws that lock the gas block on the barrel, making sure that everything stays aligned. Wojtek gas blocks should be fastened and ‘hand-tight,’ but not excessively tightened
  9. Using a small dollop of Blue Loctite (Loctite 243), secure the set screws. Allow the Loctite to set for at least 15 minutes.
  10. Lastly, reinstall your handguard. You have upgraded your gas block!

Tuning Your Adjustable Gas Block

What you want to achieve:

A rifle that cycles completely, with the appropriate amount of pressure.

What to look out for:

Under-gassing. Not enough gas pressure to completely cycle your rounds.

Over-gassing.  Too much gas pressure, resulting in increased wear and tear on your rifle.

Tuning Process

  1. Make sure that your new adjustable gas block is properly installed; check its alignment and if it is snugged in place.
  2. Once everything is in place, loosen the front set screws that hold the gas block in place. Then, tighten the gas adjustment screw in until the screw stops, but not tightly (this blocks most of the gas from entering the gas tube).
  3. Shoot the rifle in a safe area, pointing to a safe direction with one round in the magazine. Expect the bolt not to lock in place, as there isn’t enough gas to complete the cycle.
  4. Turn the adjustment screw one full 360-degree turn and fire a round. Repeat this until the bolt locks open. When the bolt locks after firing, this you have enough pressure to complete the cycle of your rifle.
  5. Open the adjustment screw just about 1/2 turn more. Tighten the front set screws that secure the block and make sure that the adjustment screws are locked in place.
  6. Fire several more rounds (10 is recommended) after you are done with the adjustments. Make sure that the rifle is ejecting and functioning correctly.
  7. The bolt should lock open on an empty magazine when you fire your last round.

One Last Tip

If there’s anyone that knows the AR-15 platform, it’s the US military. As a special offer for our readers, you can get the Official US Army Manual for AR-15/M4/M16 right now – for free. Click here to snag a copy.

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