Changing a gas block on an AR-15 can seem daunting, but with the right tools and a methodical approach, it's a manageable task for even moderately experienced gunsmiths. This guide provides a step-by-step process, emphasizing safety and precision. Always prioritize safety and ensure your firearm is unloaded before beginning any work.
Tools You'll Need
Before you start, gather the necessary tools:
- AR-15 Upper Receiver: This is the component housing the gas block.
- New Gas Block: Ensure it's compatible with your barrel's diameter and type (low-profile or standard).
- Armorer's Wrench: Specifically designed for AR-15 components, this wrench prevents damage to the barrel nut.
- Punch (Brass is recommended): To help remove the gas tube pin.
- Mallet or Hammer: Used gently with the punch.
- Gas Tube Wrench (Optional): Facilitates gas tube removal if it's difficult to remove by hand.
- Torque Wrench: Crucial for tightening the gas block to the correct specification. Incorrect torque can damage your barrel.
- Cleaning Kit: To clean the upper receiver before reassembly.
- Safety Glasses: Protect your eyes from flying debris.
- Gloves: Protect your hands.
Step-by-Step Guide to Changing Your AR-15 Gas Block
This guide assumes familiarity with basic AR-15 disassembly. If you are unsure about any step, consult a professional gunsmith.
1. Disassemble the Upper Receiver
- Ensure the firearm is unloaded. Double-check, then triple-check!
- Remove the bolt carrier group (BCG) from the upper receiver.
- Detach the charging handle.
- Carefully remove the gas tube. This often involves pushing out a gas tube retaining pin. Use the brass punch and mallet to gently tap the pin out. Some gas tubes may simply slide off.
2. Removing the Old Gas Block
- Low-Profile Gas Blocks: These typically require loosening set screws before removal. Use the appropriate size Allen wrench to loosen these screws. Once loose, the gas block should slide off the barrel.
- Standard Gas Blocks: These often require more force. Some may have set screws, while others may be pinned or soldered. If your gas block is pinned, carefully drill out the pins (being extremely cautious not to damage the barrel). If soldered, you may need to use heat to remove it—this is best left to an experienced gunsmith.
3. Installing the New Gas Block
- Low-Profile Gas Blocks: Align the new gas block with the barrel and carefully slide it into place. Tighten the set screws to the manufacturer's recommended torque specification using a torque wrench. Do not overtighten.
- Standard Gas Blocks: Installation mirrors the removal process in reverse. Ensure proper alignment and secure fastening using pins or soldering (again, soldering should be done by a professional).
4. Reassemble the Upper Receiver
- Reinstall the gas tube, ensuring it's properly seated. If it's a push-pin style, gently tap the pin back in with the brass punch and mallet. Avoid excessive force.
- Reattach the charging handle.
- Reinstall the bolt carrier group.
- Thoroughly inspect your work before firing the weapon.
Safety Precautions
- Always handle firearms safely. Never point a firearm at anything you don't intend to shoot.
- Wear safety glasses and gloves.
- Use the correct tools. Improper tools can damage your firearm.
- Follow the manufacturer's instructions.
- If you're unsure about any step, consult a professional gunsmith.
Conclusion
Replacing a gas block on an AR-15 requires patience, precision, and the right tools. By following this detailed guide and prioritizing safety, you can successfully complete this task. Remember, if you're uncomfortable with any aspect of this process, it's always best to seek professional help from a qualified gunsmith. Improper installation can lead to malfunctions and potentially dangerous consequences.
