AR-15 Parts and Accessories

AR Parts Kits

At 3CR Tactical, we offer a wide selection of AR parts kits to help you build, upgrade, or maintain your AR-15 platform. Whether you’re a first-time builder or an experienced firearm enthusiast, our high-quality parts kits provide everything you need to customize your rifle to your exact specifications. From lower parts kits to complete build kits, we’ve got you covered.

Barrels and Parts

BCG, Bolts and Parts

At 3CR Tactical, we appreciate the critical role AR bolts play in your firearm’s performance and reliability. We’ve meticulously curated our selection to offer you a range of AR bolts that cater to your specific needs. Dive into our collection and discover the foundation of a dependable and efficient firearm.

AR Buffer Tubes and Kits

Buffer Tubes and Kits

AR Build Kits

Building your own AR-15 is one of the most rewarding experiences for firearm enthusiasts, and at 3CR Tactical, we make the process easier with our high-quality AR build kits. Whether you’re a seasoned builder or new to the world of firearms assembly, our kits provide everything you need to craft a fully functional, reliable, and customizable AR-15 from scratch.

Butt Stocks

When it comes to enhancing the performance and ergonomics of your AR platform, the choice of a butt stock is a critical decision. 3CR Tactical proudly presents a wide selection of AR butt stocks to cater to the diverse needs and preferences of firearm enthusiasts. Explore our extensive collection of butt stocks, each designed with precision and quality in mind.

Charging Handles

AR-15 and AR-10 charging handles — mil-spec replacements, ambidextrous upgrades, extended-latch options. Inventory covers the 5.56/.223 platform and the .308/7.62 LR platform. Pick by platform and how you run the gun.

Mil-spec vs upgraded

Standard GI / mil-spec — fits any AR-15 or M16 upper. The right-side latch is fine for right-handed shooters running an iron-sight or low-power optic setup. Cheapest replacement when yours breaks.
Ambidextrous dual-latch — adds a left-side latch so southpaws and shooters running magnified optics can charge with their support hand without breaking grip. Most ambi handles use a larger latch surface so you can grab it with gloves.
Extended latch — same body as mil-spec but with an oversized latch for faster manipulation. A middle-ground upgrade if you want better ergonomics without the cost of a full ambi handle.
AR-10 / .308 platform — AR-10 charging handles are physically larger than AR-15 handles. Verify your upper is .308 / LR-308 pattern before ordering — DPMS-pattern uppers and Armalite-pattern uppers use the same charging handle, but the rest of the upper is not interchangeable.

The handle works with the BCG

Your charging handle and bolt carrier group work as a system — a sticky BCG makes any handle feel heavy. If you are upgrading the handle because charging feels gritty, check the BCG first. Our BCG guide covers what to look for. If you are building from scratch, see our sub-$400 AR-15 build list for a sane parts breakdown.

Gas Blocks and Gas Tubes

AR Gas blocks, gas tubes and other parts related to the direct impingement mechanism of the AR platform.

AR Grips

Lower Receivers and Parts

AR-15 lower parts kits and related components. A lower parts kit (LPK) contains everything below the upper receiver except the trigger group, stock, pistol grip, and lower receiver itself — fire control parts, springs, detents, takedown pins, bolt catch, magazine catch, and safety selector. Required for every AR-15 build.

What an LPK includes

Fire control parts — hammer, trigger, disconnector, and their springs. Standard kits ship with mil-spec single-stage fire control. Upgrade to a drop-in trigger separately if you want a lighter or two-stage pull.
Pins and detents — front and rear takedown pins, pivot pin detent, takedown pin detent, hammer and trigger pins, safety detent, buffer retainer pin and spring.
Bolt catch and magazine catch — bolt catch, bolt catch plunger, bolt catch roll pin, magazine catch button, magazine catch spring, magazine release.
Safety selector — safety lever, safety detent, safety detent spring. Some enhanced kits include an ambi safety selector instead.

Standard vs enhanced kits

Standard mil-spec LPKs (like the Spike's Tactical kit) use stamped-steel parts and are the right call for a budget build or a beater rifle. Enhanced kits (like Strike Industries Enhanced LPK) substitute machined or upgraded parts for the bolt catch, magazine release, and takedown pins — worth the extra spend if you want anti-walk pins or improved ergonomics.

Where the LPK fits in the build

The LPK is one of the last items you install on a stripped lower. See our sub-$400 AR-15 build list for a parts breakdown that puts the LPK in context, and our AR-15 accessories guide for upgrade priorities after the rifle is functional. Pair the LPK with a handguard sized to your barrel and gas system.

State laws on lower receivers and certain configurations vary. Verify local regulations before purchasing or building.

Muzzle Devices

AR-15 muzzle devices — flash hiders, muzzle brakes, compensators, and blast shields. Most inventory is 1/2x28 for 5.56/.223 barrels; some 9mm and .308 options in 1/2x36 and 5/8x24. Pick by what you need the device to do: hide flash, reduce recoil, reduce muzzle rise, or some combination.

Three jobs, three devices

Flash hider — A2 birdcage and similar designs break up the muzzle flash so you stay night-adapted and harder to spot. Minimal effect on recoil or muzzle rise. Default choice for general-purpose carbines.
Muzzle brake — side and rear ports redirect gas to push the rifle forward, reducing felt recoil. Louder and produces more side concussion (noticeable at indoor ranges and for shooters next to you). Best for precision and competition use.
Compensator — top ports vent gas upward to keep the muzzle flat through the string. Most "hybrid" muzzle devices combine brake and comp functions. Best for fast follow-up shots and rifle-class competition.

Thread pitch

5.56/.223 AR-15 barrels use 1/2x28. AR-10 / .308 barrels use 5/8x24. AR-9 9mm barrels typically use 1/2x28 or 1/2x36 depending on the manufacturer — verify the stamp on your barrel before ordering. Thread pitch matters more than caliber: a 5.56 muzzle device will physically thread onto a 9mm 1/2x28 barrel, but the bore is undersized for 9mm projectiles. Use a 9mm-specific device for a 9mm carbine.

For more on AR muzzle setups see our handguard comparison (free-float handguards expose more of the muzzle device and matter for brake clearance) and our AR-15 accessories roundup.

Scopes & Sights

AR Sights and Scopes

AR Small Parts

AR Triggers

The world of firearms is a realm of constant evolution, with enthusiasts and professionals alike seeking to optimize their shooting experience. Within this realm, a critical component that often garners attention is the AR trigger. AR triggers play a pivotal role in accuracy, control, and overall shooting satisfaction. In this comprehensive guide, we will delve into the intricacies of AR triggers, examining their importance, types, customization options, and the factors to consider when selecting the ideal trigger for your AR platform.

Handguards

Uppers and Parts

Find stripped and assembled AR-15 upper receivers from brands like Aero Precision, Spike's Tactical, BCM, and more. Whether you are building from scratch or upgrading an existing rifle, our selection includes mil-spec forged uppers, billet slick-side receivers, and complete assembled uppers with barrels and handguards pre-installed. All AR upper receivers ship with free shipping from Florida.