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Rifle Parts Receiver Parts Buffer Tube Parts Buffer Tube Hardware FORWARD CONTROLS DESIGN A5 CASTLE NUT, BURNT BRONZE Support

The A5 Castle Nut by Forward Controls Design is 0.1" longer, features deeper staking notches, and ensures compatibility with Vltor A5 systems for reliable performance.
-6 %

FORWARD CONTROLS DESIGN A5 CASTLE NUT, BURNT BRONZE

697566711183 430103540

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Variations:

Variations:

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The A5 Castle Nut by Forward Controls Design is 0.1" longer, features deeper staking notches, and ensures compatibility with Vltor A5 systems for reliable performance.
A5 CASTLE NUT - A5 CASTLE NUT, BURNT BRONZE
46.9 GBP 0 £46.90 * £49.90
Backorderable
Color: Burnt Bronze Make: AR-15 Material: Steel Product no.: 430103540
Backorderable
46.9 GBP 0 £46.90 * £49.90
The CN5F A5 Castle Nut is 0.1" longer for better compatibility with Vltor A5 systems, featuring deeper staking notches and robust 4140 PH steel construction.
A5 CASTLE NUT - A5 CASTLE NUT, BLACK
42.9 GBP 0 £42.90 *
Backorderable
Color: Black Make: AR-15 Material: Steel Product no.: 430103538
Backorderable
42.9 GBP 0 £42.90 *
The A5 Castle Nut by Forward Controls Design is 0.1" longer, features deeper staking notches, and ensures full stock collapse on Vltor A5 systems.
A5 CASTLE NUT - A5 CASTLE NUT, OLIVE DRAB GREEN
49.9 GBP 0 £49.90 *
Backorderable
Color: Olive Drab Green Make: AR-15 Material: Steel Product no.: 430103541
Backorderable
49.9 GBP 0 £49.90 *
The CN5F A5 Castle Nut offers enhanced compatibility, deeper staking notches, and a robust design for secure fitting on Vltor A5 systems, proudly made in the USA.
A5 CASTLE NUT - A5 CASTLE NUT, FLAT DARK EARTH
Not available
Color: Flat Dark Earth Make: AR-15 Material: Steel Product no.: 430103539
Not available
47.9 GBP 0 £47.90 *
42.9 49.9 4 GBP
-6 %
MSRP £49.90
46.9 GBP £46.90

Prices inclusive of duty & VAT.

Product no.: 430103540

Mfr. No.: CN5F BB

697566711183 CN5F (Castle Nut, A5, Forward Controls) is an extended version of CNF Forward Controls Design (FCD) have been making since 2018. CN5F is designed specifically for the superb Vltor A5 system, CN5F is 0.1" longer, and is as long as FCD can make a castle nut while ensuring backward compatibility, and the stock's ability to fully collapse on Vltor's RE-A5 and FCD's RE5F. Note: not all stocks will fully collapse on A5 compatible REs. For more information on the differences between RE-A5, RE5F and RE10/A5SR, please follow this link: https://www.forwardcontrolsdesign.com/Vltor-RE-A5-vs-RE10-A5SR_ep_78-1.html CN5F aims to cover as much of the threaded area of a receiver extension (RE) as possible. It could be made longer, but it will run into backward compatibility issues with some REs' timing when installing the castle nut and end plate on the RE. CN5F is made specifically for the Vltor A5 system, and it will allow even the longest carbine stocks to fully collapse on RE-A5 and FCD's RE5F. While CN5F will also work on standard TDP spec length RE, the additional length of the castle nut will prevent the carbine stock to fully collapse. Other than its length, CN5F shares common features with its smaller brother, CNF. The TDP spec castle nut is a simple and robust fastener that is almost perfect for the job it's tasked to perform. Over the years, FCD have consistently come up with two minor gripes, first is its staking notches seem rather shallow and short, second is FCD don't enjoy using the castle nut's wrench notches as serrations (FCD's fingers invariably find their way to these sharp cutouts) to rotate it towards to the end plate while installing it. CN5F (Castle Nut, Forward Controls) is based on the TDP spec castle nut, with couple of changes: 0.1" longer. Staking notches angle changed from 45 to 30 degrees, this results in longer (25% longer than TDP spec) and deeper notches than found on TDP castle nuts. Number of staking notches increased from 3 to 4, spaced equally on the CNF. The castle nut is to be staked in two places, FCD are not advocating staking in more than two places, CNF's 4 staking notches mean that, at all times, 3 will be visible and available for staking, it simply gives the user more staking location options. Coarse serrations on the wrench side of the nut, a single use feature to make it easier while rotating the CNF towards the end plate. It is FCD’s opinion that a castle nut should be staked per TM, CNF's and CN5F's longer and deeper notch reinforces the belief, that once installed and staked, it will not loosen without the user's deliberate action. Forward Controls Design like the idea of quick detach, but some things on an AR are meant to stay put, and considerable effort was made to ensure that by the original designers. CNF and CN5F are a continuation and evolution in that direction. CN5F is billet machined in 4140 PH steel, and black nitrided (Cerakoted FDE, OD green, and burnt bronze also available). As with everything Forward Controls Design produces, it is proudly made in the USA. Weight: 0.51oz Material: 4140 PH Made in USA
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Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy
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42.9 49.9 4 GBP
Description Specification Customers reviews Accessories

FORWARD CONTROLS DESIGN A5 CASTLE NUT, BURNT BRONZE

-6 %
MSRP £49.90
46.9 GBP £46.90

Prices inclusive of duty & VAT.

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10+
-6 %
MSRP £49.90
£46.90

Prices inclusive of duty & VAT.

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Backorderable, delivery time approx. 4-12 weeks from the USA warehouse.

100-Day Return Policy

Description:

Upgrade your firearm with the A5 Castle Nut from Forward Controls Design!

The A5 Castle Nut, designed by Forward Controls Design, offers an extended and enhanced solution for your Vltor A5 system. The CN5F model is an improved version of the original CNF castle nut, developed since 2018, and is specifically tailored to ensure compatibility with Vltor's RE-A5 and FCD's RE5F.

Key Features:

  • Length: The CN5F is 0.1" longer than its predecessor, maximizing the coverage of the threaded area of the receiver extension (RE).
  • Staking Notches: Features 4 staking notches, angled from 45 to 30 degrees, providing deeper and longer notches (25% longer than TDP spec).
  • Coarse Serrations: Designed on the wrench side for easier rotation towards the end plate during installation.
  • Material: Constructed from high-quality 4140 PH steel and finished with black nitriding, with options for Cerakoted FDE, OD green, and burnt bronze.
  • Weight: Weighs only 0.51oz, making it a lightweight addition to your firearm.

The CN5F castle nut is engineered to allow even the longest carbine stocks to fully collapse on compatible REs, while also being suitable for standard TDP spec length REs, although the added length may restrict full collapse in certain configurations.

Forward Controls Design believes in the importance of secure installation; thus, the CN5F is designed to be staked per TM standards, ensuring that once installed, it remains securely in place without loosening unless intentionally adjusted by the user.

As always, Forward Controls Design proudly manufactures their products in the USA, reflecting their commitment to quality and performance.

For more information on the differences between RE-A5, RE5F, and RE10/A5SR, please visit: Forward Controls Design Comparison.



Top takeaways

  1. The CN5F is an extended castle nut designed specifically for the Vltor A5 system, adding 0.1" in length for better compatibility and coverage on receiver extensions.
  2. It features improved staking notches that are 30 degrees, 25% longer and deeper than TDP spec, with four equally spaced notches for more staking options.
  3. CN5F is constructed from 4140 PH steel, available in various colors including burnt bronze, and is manufactured in the USA by Forward Controls Design LLC.

Attributes

  • Colour: 
    Burnt Bronze
  • Material: 
    Steel
  • Weapon type: 
    AR-15
  • Delivery weight: 0.581kg
  • Shipping height: 51mm
  • Shipping width: 83mm
  • Shipping length: 140mm
  • UPC: 697566711183

Item details

Made in USA

Customers reviews

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Variations:

-6 %
The A5 Castle Nut by Forward Controls Design is 0.1" longer, features deeper staking notches, and ensures compatibility with Vltor A5 systems for reliable performance.
A5 CASTLE NUT - A5 CASTLE NUT, BURNT BRONZE
46.9 GBP 0 £46.90 * £49.90
Backorderable
Color: Burnt Bronze Make: AR-15 Material: Steel Product no.: 430103540
Backorderable
46.9 GBP 0 £46.90 * £49.90
The CN5F A5 Castle Nut is 0.1" longer for better compatibility with Vltor A5 systems, featuring deeper staking notches and robust 4140 PH steel construction.
A5 CASTLE NUT - A5 CASTLE NUT, BLACK
42.9 GBP 0 £42.90 *
Backorderable
Color: Black Make: AR-15 Material: Steel Product no.: 430103538
Backorderable
42.9 GBP 0 £42.90 *
The A5 Castle Nut by Forward Controls Design is 0.1" longer, features deeper staking notches, and ensures full stock collapse on Vltor A5 systems.
A5 CASTLE NUT - A5 CASTLE NUT, OLIVE DRAB GREEN
49.9 GBP 0 £49.90 *
Backorderable
Color: Olive Drab Green Make: AR-15 Material: Steel Product no.: 430103541
Backorderable
49.9 GBP 0 £49.90 *
The CN5F A5 Castle Nut offers enhanced compatibility, deeper staking notches, and a robust design for secure fitting on Vltor A5 systems, proudly made in the USA.
A5 CASTLE NUT - A5 CASTLE NUT, FLAT DARK EARTH
Not available
Color: Flat Dark Earth Make: AR-15 Material: Steel Product no.: 430103539
Not available
47.9 GBP 0 £47.90 *

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