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

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.

FORWARD CONTROLS DESIGN A5 CASTLE NUT, BLACK

697566711138 430103538

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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 compatibility with Vltor A5 systems for reliable performance.
A5 CASTLE NUT - A5 CASTLE NUT, BURNT BRONZE
49.9 GBP 0 £49.90 *
Backorderable
Color: Burnt Bronze Make: AR-15 Material: Steel Product no.: 430103540
Backorderable
49.9 GBP 0 £49.90 *
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
42.9 GBP £42.90

Prices inclusive of duty & VAT.

Product no.: 430103538

Mfr. No.: CN5F BLK

697566711138 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.

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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, BLACK

42.9 GBP £42.90

Prices inclusive of duty & VAT.

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10+
£42.90

Prices inclusive of duty & VAT.

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2
3
4
5
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8
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10+

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

100-Day Return Policy

Description:

Introducing the A5 Castle Nut from Forward Controls Design

The CN5F Castle Nut is an innovative solution designed specifically for the Vltor A5 system, enhancing compatibility and functionality for your firearm.

Product Features:

  • Length: 0.1" longer than standard TDP spec castle nuts.
  • Staking Notches: Angle changed from 45 to 30 degrees, resulting in notches that are 25% longer and deeper.
  • Increased Staking Notches: Now features 4 staking notches, providing more options for secure installation.
  • Coarse Serrations: Located on the wrench side for easier rotation towards the end plate.
  • Material: Manufactured from 4140 PH steel and black nitrided for durability.
  • Weight: 0.51 oz.
  • Made in: Proudly manufactured in the USA.

The CN5F aims to maximize the threaded area coverage of a receiver extension (RE) while ensuring backward compatibility with various stocks. It's designed to allow even the longest carbine stocks to fully collapse on RE-A5 and FCD's RE5F. Please note that not all stocks will fully collapse on A5 compatible REs.

FCD has taken feedback from users into account, addressing common concerns such as shallow staking notches and the usability of the castle nut's wrench notches. The CN5F is a testament to Forward Controls Design's commitment to quality and functionality in firearm accessories.

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



Top takeaways

  1. The CN5F is an extended castle nut designed specifically for the Vltor A5 system, providing full stock collapse on Vltor's RE-A5 and FCD's RE5F.
  2. It features a 0.1" longer body, 30-degree staking notches for enhanced security, and is machined from 4140 PH steel with a black nitride finish.
  3. This product is made in the USA by Forward Controls Design LLC and is compatible with AR-15, but may prevent full stock collapse on standard TDP spec length receiver extensions.

Attributes

  • Colour: 
    Black
  • Material: 
    Steel
  • Weapon type: 
    AR-15
  • Delivery weight: 0.572kg
  • Shipping height: 51mm
  • Shipping width: 83mm
  • Shipping length: 140mm
  • UPC: 697566711138

Item details

Made in USA

Customers reviews

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Variations:

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 compatibility with Vltor A5 systems for reliable performance.
A5 CASTLE NUT - A5 CASTLE NUT, BURNT BRONZE
49.9 GBP 0 £49.90 *
Backorderable
Color: Burnt Bronze Make: AR-15 Material: Steel Product no.: 430103540
Backorderable
49.9 GBP 0 £49.90 *
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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