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AT3 Tactical

AT3 Castle Nut for AR-15 Buffer Tubes

Regular priceFrom $5.99 USD
Shipping calculated at checkout.

Firearm-compatible AR-15 castle nut with steel construction, Mil-Spec threading, staking notches, wrench cutouts, and multiple color options.

Color:

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⚠️ 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

Secure and Reliable Fit

Ensure rock-solid stability for your AR-15 buffer tube and stock assembly with this high-quality steel castle nut. Designed for precise fitment and durability, this MIL-SPEC castle nut features standard armorer’s wrench cutouts for easy installation, along with staking notches for added security. Whether you’re building a new rifle, upgrading components, or replacing a worn-out nut, this affordable and rugged castle nut is a must-have.


Key Features:

High-Strength Steel Construction – Provides maximum durability and long-lasting performance.
MIL-SPEC Threading – Ensures secure compatibility with standard AR-15 buffer tubes.
Staking Notches for Secure Installation – Prevents loosening over time, maintaining reliability in demanding conditions.
Compatible with Armorer’s Wrench – Allows for hassle-free installation and removal.
Multiple Cerakote™ Color Options – Add a custom touch to your rifle with FDE, OD Green, Pink, Red, Blue, Burnt Bronze, Tungsten, or Titanium.
Black Phosphate Finish Option – Classic, corrosion-resistant finish for a sleek and tactical look.
Perfect for AR-15 Builds & Upgrades – Works seamlessly with all MIL-SPEC AR-15 lower receivers and buffer tubes.


Available Finishes:

🎨 Customize your build with premium Cerakote™ finishes:

🔹 Black: Phosphate finish for a classic, durable look
🔹 Flat Dark Earth (FDE): H-267 Magpul® Flat Dark Earth
🔹 OD Green (ODG): H-232 Magpul® OD Green
🔹 Pink: H-224 SIG™ Pink
🔹 Red: H-167 USMC Red
🔹 Blue: H-171 NRA Blue
🔹 Burnt Bronze: H-148 Burnt Bronze
🔹 Tungsten: H-237 Tungsten
🔹 Titanium: H-170 Titanium


Built for AR-15 Enthusiasts & Professionals

🔸 Ideal for rifle builders, gunsmiths, and AR-15 enthusiasts
🔸 Designed for secure fitment on MIL-SPEC buffer tubes
🔸 Ensures long-term durability and enhanced performance

When reliability and stability matter, trust this steel castle nut to lock your buffer tube assembly in place.

Upgrade your AR-15 today with a battle-tested castle nut that won’t let you down!AT3

Specifications

  • Platform Compatibility
    Mil-Spec AR

Reviews & Questions (1)

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