This is from Brave, where are the casings, again?
Ar15 shell casing ejection
The direction of spent case ejection from an AR-15 rifle is referred to as the “ejection pattern.” This aspect is crucial for shooters, especially those who handle their firearms frequently, as hot brass cases can cause burns.
Desirable Ejection Angle
According to various sources, a conventional and ideal ejection pattern for an AR-15 is between 3:00 and 4:30 o’clock, measured from the ejection port (center) to the stock (6:00). This range allows for efficient case ejection, reducing the risk of cases bouncing off nearby surfaces or hitting bystanders.
Variations and Considerations
Some AR-15s may eject cases between 12:00 and 3:00 o’clock, which is still within acceptable parameters. However, ejection patterns outside this range can indicate issues with the rifle’s functioning, such as over-gassing (0-90 degree angle) or improper extraction.
Factors Affecting Ejection Pattern
The ejection pattern can be influenced by various factors, including:
Buffer spring and BCG (Bolt Carrier Group) combinations
Gas block and upper receiver design
Ammunition type and pressure
Conclusion
In summary, a well-functioning AR-15 should eject spent cases between 3:00 and 4:30 o’clock. Deviations from this range may indicate potential issues with the rifle’s operation. Understanding and adjusting these factors can help achieve a reliable and safe ejection pattern.