Unlock the Secret of AR 9 Glock's Last Round Bolt Hold Open
Table of Contents:
- Introduction
- Understanding the Last Round Vault Hold Open Mechanism
- Different Provisions for Last Round Vault Hold Open in AR9s
3.1 PSA Build with Aero Precision Upper
3.2 Foxtrot Mic Complete Pistol
- Comparison of Last Round Vault Hold Open Mechanisms
4.1 Glock Magazine Follower Design
4.2 Foxtrot Mic's Patented Lower Receiver Mechanism
4.3 PSA Build with Aero Precision Upper Mechanism
- Compatibility Issues
5.1 Compatibility between Foxtrot Mic Lower Receiver and PSA Upper Receiver
5.2 Compatibility between Foxtrot Mic Upper Receiver and PSA Lower Receiver
- Options for Adding Last Round Vault Hold Open
6.1 Replacing the Upper Receiver
6.2 Replacing the Lower Receiver
- Popular and Accessible Options
- Conclusion
Understanding the Last Round Vault Hold Open Mechanism
The last round vault hold open feature in AR9s, especially those using Glock magazines, is a crucial aspect to consider for firearms enthusiasts. This mechanism ensures that the bolt remains open after firing the last round, indicating that the magazine is empty and needs to be reloaded. In this article, we will explore the different provisions available for last round vault hold open in AR9s, specifically focusing on a PSA build with an Aero Precision upper and a complete pistol from Foxtrot Mic.
Different Provisions for Last Round Vault Hold Open in AR9s
AR9s equipped with last round vault hold open functionality can be achieved through various mechanisms. Let's delve into two popular options: the PSA build with Aero Precision upper and the complete pistol from Foxtrot Mic.
3.1 PSA Build with Aero Precision Upper
The PSA build, combined with an Aero Precision upper, incorporates a new frontier armory-style last round vault hold open mechanism. This mechanism is entirely captured within the upper receiver. By utilizing a hook on the inside of the upper and a bar on the outside, the mechanism interfaces with the bolt hold open catch. However, it is important to note that the PSA build and the Foxtrot Mic lower receiver are not compatible due to differences in their design.
3.2 Foxtrot Mic Complete Pistol
Foxtrot Mic takes a different approach with their patented last round vault hold open mechanism. Instead of integrating it within the upper receiver, they have entirely captured the mechanism within the lower receiver. Their design eliminates the need for a reach-around mechanism, ensuring seamless operation. The Foxtrot Mic upper and PSA lower, which lack any provisions for last round vault hold open, are compatible with each other.
Comparison of Last Round Vault Hold Open Mechanisms
Let's compare the two mechanisms used to achieve last round vault hold open functionality in AR9s - the Glock magazine follower design and Foxtrot Mic's patented lower receiver mechanism.
4.1 Glock Magazine Follower Design
The last round vault hold open feature in AR9s utilizing Glock magazines is dependent on the design of the magazine follower. The last round bolt hold open part of the follower is located at the front. When the magazine is empty, a reach-around mechanism is required to engage the bolt hold open catch.
4.2 Foxtrot Mic's Patented Lower Receiver Mechanism
Foxtrot Mic has revolutionized the last round vault hold open mechanism by developing a patented design that integrates it entirely within the lower receiver. This design eliminates the need for a reach-around mechanism and ensures reliable and consistent operation.
4.3 PSA Build with Aero Precision Upper Mechanism
The PSA build with an Aero Precision upper utilizes a hook on the inside of the upper receiver and a bar on the outside to engage the bolt hold open catch. This mechanism is compatible with Glock magazines and provides a reliable last round vault hold open feature.
Compatibility Issues
While both the Foxtrot Mic and PSA builds offer last round vault hold open functionality, it is important to consider compatibility issues between different components.
5.1 Compatibility between Foxtrot Mic Lower Receiver and PSA Upper Receiver
The Foxtrot Mic lower receiver and PSA upper receiver are fundamentally not compatible due to their conflicting design features. The hook on the PSA upper receiver and the interface with the front of the Glock magazine follower try to occupy the same space, resulting in improper fitting or potential damage to the components.
5.2 Compatibility between Foxtrot Mic Upper Receiver and PSA Lower Receiver
On the other hand, the Foxtrot Mic upper receiver and PSA lower receiver can be interchanged without any compatibility issues. Both these components lack provisions for last round vault hold open, enabling seamless compatibility.
Options for Adding Last Round Vault Hold Open
If you wish to add last round vault hold open functionality to your AR9, there are two options to consider: replacing the upper receiver or replacing the lower receiver.
6.1 Replacing the Upper Receiver
To add last round vault hold open functionality to your AR9, you can replace the upper receiver with one that has the necessary provisions. This option ensures compatibility and allows for a reliable last round vault hold open mechanism.
6.2 Replacing the Lower Receiver
Alternatively, you can opt to replace the lower receiver with a compatible one that has an integrated last round vault hold open mechanism. This option offers simplicity and convenience, enabling a seamless upgrade.
Popular and Accessible Options
Both the options mentioned above are popular and accessible for those looking to add last round vault hold open functionality to their AR9s. It is essential to select the right components and ensure compatibility to avoid any issues or complications with the installation.
Conclusion
In conclusion, the last round vault hold open feature is an important consideration for AR9 owners, particularly those using Glock magazines. Understanding the different provisions available and ensuring compatibility between components are key factors to consider when adding this functionality. By choosing the right combination of upper and lower receivers, firearms enthusiasts can enjoy a reliable and efficient last round vault hold open mechanism for their AR9s.
Highlights:
- Last round vault hold open is a crucial feature for AR9s with Glock magazines.
- PSA build with Aero Precision upper and Foxtrot Mic complete pistol offer different provisions for last round vault hold open.
- Foxtrot Mic's patented lower receiver mechanism eliminates the need for a reach-around mechanism.
- Compatibility issues arise between different components, so selecting the right combination is crucial.
- Options for adding last round vault hold open include replacing the upper or lower receiver.
- Popular and accessible options ensure a seamless upgrade for AR9 owners.
FAQ:
Q: Can I use a Foxtrot Mic upper receiver with a PSA lower receiver?
A: Yes, Foxtrot Mic upper receivers are compatible with PSA lower receivers.
Q: Can I use a PSA upper receiver with a Foxtrot Mic lower receiver?
A: No, PSA upper receivers are not compatible with Foxtrot Mic lower receivers.
Q: Is it necessary to have last round vault hold open in an AR9?
A: It is not necessary but can be a useful feature, especially for quick magazine changes and magazine management.
Q: Can I retrofit last round vault hold open functionality on my existing AR9?
A: Yes, you can retrofit by replacing the upper or lower receiver with compatible ones that have the necessary provisions.
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