AR-15 LPK Takedown Pin

Description

OVERVIEW – MIL-SPEC REAR TAKEDOWN PIN FOR SECURE UPPER AND LOWER RECEIVER CONNECTION

The AR-15 LPK Takedown Pin is the rear pin that locks your AR-15 upper and lower receivers together, ensuring a tight, wobble-free fit and safe, reliable function. Located at the rear of the lower receiver just above the buffer tube, this pin is pulled out slightly to allow the upper receiver to pivot open on the front pivot pin for cleaning, maintenance, and breakdown, and pushed back in to lock the rifle closed for firing. If your original takedown pin is lost, damaged, bent, or showing wear in the detent grooves, this mil-spec replacement restores proper lockup, eliminates upper/lower play, and ensures your rifle stays securely assembled under recoil and hard use. Without a correctly dimensioned takedown pin, your upper and lower can develop excessive play, rattling, and even separate during firing — a dangerous condition.

This takedown pin is manufactured to exact mil-spec dimensions from solid steel and finished with a durable parkerized coating for corrosion resistance and smooth operation. The pin features precisely machined detent grooves that engage with the takedown pin detent and spring inside your lower receiver, providing positive retention in both the open and closed positions — the pin snaps into place and stays put until you intentionally pull it. The head is knurled and slightly extended for easy finger manipulation without tools, yet low-profile enough to avoid snagging on gear. It is a direct drop-in replacement for all standard AR-15, M4, M16, and AR-10 lower receivers that use standard .250-inch diameter takedown pins, including forged, billet, and 80% lowers. Whether you are completing a lower build, replacing a worn pin, or keeping spare LPK components on your workbench, this takedown pin delivers the correct fit, function, and durability for safe, reliable rifle assembly.

WHY CHOOSE THIS AR-15 LPK TAKEDOWN PIN

Secure lockup, smooth function, mil-spec reliability.

1. Exact Mil-Spec .250″ Diameter with Precision Detent Grooves for Positive Retention: The AR-15 takedown pin system relies on precise tolerances to function correctly. This pin is machined to the standard .250-inch (1/4″) diameter with tight tolerances for a snug but smooth fit through both the upper and lower receiver takedown pin holes. The detent grooves are machined at the exact location and depth to interface correctly with the takedown pin detent inside your lower receiver. This creates the characteristic snap that holds the pin in both the closed position (pin fully inserted, upper and lower locked together) and the open position (pin pulled out to the detent stop, allowing the upper to pivot). Too shallow a groove and the pin will walk out on its own; too deep and the pin will be difficult to pull. This pin’s grooves are cut to mil-spec depth for optimal retention — the pin stays firmly seated during firing, handling, and drops, yet can still be pulled with finger pressure when you need to break down the rifle. The shaft is polished smooth to prevent binding or scratching inside the receiver holes, ensuring smooth operation even after thousands of open/close cycles.

2. Solid Steel Construction with Parkerized Corrosion-Resistant Finish: This takedown pin is made from solid carbon steel, not cast or MIM metal that can crack or deform. The steel is heat-treated for strength and durability, ensuring the pin will not bend, mushroom, or wear prematurely even under heavy use, repeated takedowns, and exposure to recoil forces. The parkerized finish provides excellent corrosion resistance against moisture, humidity, gun oils, and cleaning solvents, and gives the pin a classic matte black/gray military appearance that matches your lower receiver and other LPK components. The knurled head provides a positive grip for finger manipulation, even with gloves or sweaty hands, while maintaining a low-profile design that will not snag on slings, gear, or clothing. The edges are deburred and slightly chamfered to prevent sharp edges from scratching your receiver or cutting your fingers during manipulation. This is a true duty-grade replacement part built to last the life of your rifle, not a cheap bulk pin that will wear out after a few months.

3. Direct Drop-In Replacement for All Standard AR-15 Lowers and Essential Spare for Builds: This takedown pin is a direct replacement for any standard AR-15, M4, M16, and AR-10 lower receiver that uses mil-spec .250″ takedown pins — which includes virtually all forged, billet, and 80% lowers on the market. Installation takes seconds: ensure your takedown pin detent and spring are installed in the lower receiver’s rear channel (in the buffer tube area), then slide the takedown pin through the lower receiver’s rear takedown holes, depressing the detent as you go. The pin will snap into place when fully seated. No gunsmithing, fitting, or special tools required. This pin is essential for completing stripped lower builds, replacing a lost pin, upgrading a worn or damaged pin, or keeping as a spare in your armorer’s kit. Many builders also keep an extra takedown pin because they are small and easily lost during cleaning or field stripping. Whether you are finishing an 80% lower, assembling a lower parts kit, or performing routine maintenance, this takedown pin ensures your upper and lower stay locked together securely for safe, reliable shooting.

RESTORE SECURE UPPER/LOWER LOCKUP

The AR-15 LPK Takedown Pin delivers mil-spec .250″ diameter, precise detent grooves, and parkerized steel durability for reliable rifle assembly.

SPECIFICATIONS

Type: AR-15 LPK Takedown Pin – Rear Takedown Pin. Material: Solid Carbon Steel – Heat Treated. Finish: Parkerized / Phosphate – Corrosion-Resistant. Diameter: .250″ (1/4″) Mil-Spec. Detent Grooves: Precision Machined for Positive Retention in Open/Closed Positions. Head: Knurled for Easy Finger Manipulation – Low Profile. Compatibility: All Standard AR-15 / M4 / M16 / AR-10 Lower Receivers Using Mil-Spec .250″ Takedown Pins – Includes Forged, Billet, 80% Lowers. Function: Locks Upper and Lower Receivers Together.