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Anderson Manufacturing  |  SKU: AM-26  |  UPC: 05560610

Anderson Manufacturing AR-15 Buffer Tube Castle Nut 0.1 lb

Regular price $9.99 USD
Shipping calculated at checkout.

Firearm-compatible AR-15 castle nut with steel construction, manganese phosphate finish, wrench cutouts, and MIL-SPEC buffer tube fitment.

By continuing to checkout, you agree to our Terms of Service, Shipping Policy, Return Policy, and product restrictions.

⚠️ Sold for sporting and training applications. Customer is responsible for ensuring compliance with all applicable local laws and regulations. See Terms .

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🎯 Real magfed support

🚚 Shipping & Delivery

Most in-stock items ship within 3 business days.

Special order items are typically processed within 14 business days (excluding weekends and holidays).

Custom items may require additional time depending on production schedules.

If you’d like to receive your order sooner, please select an expedited shipping option at checkout.

Some products ship directly from the manufacturer, and an equivalent carrier or service level will be chosen to match your selected shipping speed.

Shipping delays caused by carriers are outside our control, but we’ll always help track updates.

See our Shipping Policy for details.

🔄 Returns, Exchanges & Warranty

Returns are accepted within 14 days for items that are unused, unopened, and in original packaging with no damage.

A restocking fee applies, but it may be partially waived if store credit is selected instead of a refund to the original payment method.

Custom builds, sale items, and hazardous goods are final sale.

Warranty Coverage: Manufacturer warranties apply to all standard products. Any defects, malfunctions, or performance issues are handled directly by the manufacturer per their terms.

HR Tactical Innovations covers a Fitment & Functionality Guarantee on all custom or modified items — if a verified production error occurs, we’ll replace the item.

View our Refund Policy for full details.

🌍 International Shipping

We ship worldwide to Canada, Mexico, Europe, Asia, and Oceania, including:

🇨🇭 Switzerland • 🇨🇿 Czechia • 🇩🇪 Germany • 🇩🇰 Denmark • 🇪🇸 Spain • 🇫🇮 Finland • 🇫🇷 France • 🇬🇧 United Kingdom • 🇭🇰 Hong Kong SAR • 🇮🇪 Ireland • 🇮🇹 Italy • 🇯🇵 Japan • 🇰🇷 South Korea • 🇲🇾 Malaysia • 🇳🇱 Netherlands • 🇳🇴 Norway • 🇵🇱 Poland • 🇵🇹 Portugal • 🇸🇪 Sweden • 🇸🇬 Singapore • 🇦🇺 Australia • 🇳🇿 New Zealand • 🇦🇪 UAE and more.

Transit averages 2–4+ weeks depending on customs clearance. Delays caused by customs or local authorities are outside of our control. Faster transit times may be available through expedited shipping options, though this does not guarantee faster customs processing.

Import duties, VAT, taxes, and brokerage fees are not included in your order total and must be paid by the recipient.

Customers are responsible for ensuring that all items ordered comply with their country’s import laws and for obtaining any required permits or documentation prior to purchase. We do not provide guidance on country-specific import requirements.

If a package is rejected, unclaimed, or returned due to unpaid duties, missing documentation, import restrictions, or an incorrect address:

  • The order will be issued as store credit only
  • Original shipping costs are non-refundable
  • Any non-recoverable shipping or return fees may be deducted

If a shipment is lost, seized, or not returned, an insurance claim must be completed before any resolution is provided. If the claim is denied, no refund or credit will be issued.

Pressurized or restricted items will ship via ground services only where permitted.

For more information view our Shipping Policy and our Refund Policy.

Questions? Contact [email protected] before checkout.

🎖️ Military / GovX Discounts

⚙️ Product Details

Reliable Buffer Tube Security for Your AR-15 Build

The Anderson Manufacturing MIL-SPEC AR-15 Castle Nut is a critical component in securing the buffer tube and stock system to your lower receiver. Built from high-quality steel and Manganese Phosphate coated, this durable castle nut is designed to ensure a solid and reliable connection between the buffer system and the lower receiver—preventing loosening, maintaining stability, and improving long-term durability.


Key Features:

MIL-SPEC Dimensions – Compatible with all standard AR-15 buffer tubes, ensuring a secure fit.
Manganese Phosphate Finish – Provides corrosion resistance and long-lasting durability.
Precision Machined for Secure Fit – Designed for proper torque application, allowing for a rock-solid buffer system attachment.
Wrench Cutouts for Easy Installation – Castle turret-style cutouts allow a castle nut wrench to provide the necessary torque for a secure hold.
Cutout for Staking – Prevents the castle nut from loosening over time, ensuring maximum reliability.
Made in the USA – Manufactured to strict MIL-SPEC standards for uncompromising performance.


Why It Matters:

The castle nut plays a critical role in maintaining the integrity of the buffer system on an AR-15. A loose castle nut can cause instability, leading to malfunctions or premature wear. By staking the castle nut with the end plate, you mechanically lock it in place, preventing it from backing off during extended use.

For optimal installation:
🔹 Torque to 40 ft/lbs – No thread locker is required.
🔹 Position wrench cutouts away from the receiver – Align the smaller cutout with the end plate.
🔹 Stake the end plate into the castle nut – Lightly tap with a hardened punch to lock it in place while still allowing for removal if necessary.


Perfect for Any AR-15 Build

Whether you're building a new rifle or replacing a worn-out castle nut, the Anderson Manufacturing MIL-SPEC Castle Nut ensures a secure, long-lasting connection between your buffer system and receiver—so you can focus on accuracy, reliability, and performance.

Upgrade your AR-15 with a castle nut built for strength and reliability!

Specifications

  • Platform Compatibility
    Mil-Spec AR

Reviews & Questions

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