Why Is My AR-15 Failing to Eject? How Do I Fix Stovepipes?
The most common causes of failure to eject (stovepipes) are a weak or broken extractor spring, insufficient gas (undergassed), a dirty chamber or bolt, and a worn ejector or ejector spring. Start by cleaning the bolt and chamber thoroughly, then inspect the extractor spring tension and check gas block alignment.
Why It Matters
A failure to eject means the spent case is not being thrown clear of the ejection port after extraction. The case gets caught between the bolt and the ejection port, jamming the action. This malfunction completely stops the rifle from firing and requires manual clearance. In a defensive or competition context, reliable ejection is essential.
Troubleshooting ejection issues means testing multiple loads — find quality brass-case ammo to isolate the problem.
Shop 5.56/.223 Ammo at Lucky Gunner →The Detail
Failure to eject diagnostic process:
Step 1: Clean everything first
- Carbon buildup on the bolt face, in the chamber, or in the extractor channel is the most common and easiest-to-fix cause
- Clean the bolt, paying special attention to the extractor claw and the area behind it
- Clean the chamber with a chamber brush
- Lubricate the bolt carrier group properly
Step 2: Inspect the extractor
- Remove the bolt from the carrier
- Push the extractor with your thumb — it should have strong, positive spring tension
- If it feels weak or mushy, replace the extractor spring
- Check the extractor claw for chips, wear, or damage
- The extractor O-ring (if present) adds tension — make sure it is in place and not deteriorated
- Upgrade option: BCM extractor spring kit (enhanced spring plus O-ring)
Step 3: Check the ejector
- The ejector is the small plunger on the bolt face opposite the extractor
- Push it with a small punch — it should have firm spring tension and snap back quickly
- A weak ejector spring causes the case to not be kicked out with enough force
- Replace the ejector spring if it feels weak
Step 4: Evaluate gas system
- If the bolt is not traveling rearward far enough, the ejector does not have enough time/force to kick the case out
- Check gas block alignment
- Verify gas key is properly torqued (35 to 40 inch-pounds) and staked
- Try a lighter buffer
- Look for gas leaks at the gas block and gas key
Step 5: Check ammunition
- Weak or underpowered ammunition may not generate enough gas pressure
- Try a different brand of brass-cased ammunition
- Steel-cased ammunition has different extraction characteristics and may cause issues in some rifles
Build Impact
For new builds experiencing failures to eject, the most likely causes are gas block misalignment (did not verify alignment during assembly), an improperly staked gas key (gas leak), or a dry bolt (insufficient lubrication). Before blaming components, confirm assembly was done correctly. If building from scratch, invest in a quality BCG with a properly staked gas key — this alone prevents many cycling issues.