What parts do I need to build an AR-15?

To build an AR-15, you'll need upper and lower receiver parts, a bolt carrier group, barrel, gas system, buffer system, trigger assembly, and handguard.

Are your AR-15 parts mil-spec compatible?

Yes, most of our AR-15 parts are mil-spec and designed to fit standard AR-15 platforms, including lower kits, buffer tubes, and springs.

What’s the difference between mil-spec and custom AR-15 parts?

Mil-spec parts follow standard military dimensions and are interchangeable across builds. Custom parts offer upgraded features like enhanced ergonomics or aesthetics.

Do you carry parts for AR-15 pistols?

Yes, many of our parts are compatible with AR-15 pistol builds, including buffer systems, grips, and lower receiver components.

Can I replace individual AR-15 parts without re-building the whole rifle?

Absolutely. You can replace worn or damaged parts individually, such as springs, takedown pins, or selectors, without doing a full rebuild.

AR-15 Parts – Mil-Spec & Custom Rifle Components

AR-15 Mag Release

Bolt Carrier Groups

Bolt Catch

AR-15 End Plate

Gas System Parts

Recoil Parts

Safety Selector

AR-15 Springs

Takedown Pins

AR-15 Triggers

Red AR 15 Parts

AR-15 Forward Assist

Dust Cover / Ejection Port Cover

AR-15 Lower Parts Kit

AR15 Upper Parts Kit

AR-15 Barrel

**ERGO AR-15 Lower Spring Replacement Kit** $7.45

**ERGO AR-15 Upper Spring Replacement Kit** $7.45

**ERGO AR-15 Upper & Lower Spring Replacement Kit** $14.00

**Elftmann Speed Safety - Push Button AR15 Ambidextrous Safety** $37.95

**Matador Arms STINGER AR Muzzle Brake w/ Muzzle Blast Diverter** $89.99

**Geissele SSA: Super Semi-Automatic AR-15 Trigger** $240.00

**Timber Creek Outdoors AR Takedown Pin Sets** $15.99

**Timber Creek Outdoors AR Extended Magazine Release** $15.99

**Timber Creek Outdoors AR Oversized Trigger Guard** $19.19

**Timber Creek Ambidextrous Safety Selector** $31.99

**Timber Creek Outdoors QD End Plate** $15.99

**Deltac 28pc AR-15 Lower Parts Kit** $32.95

**DELTAC Ejection Port Cover kit for AR-15 (Made in USA)** $14.95

**Aim Sports Mil-Spec Flash Hider, 1/2-28** $11.95

**Timber Creek Outdoors Billet AR-15 Dust Cover** $23.95

**Aim Sports AR-15 Lower Parts Kit** $61.95

**Aim Sports AR 15 Buffer Spring** $6.95

**Timber Creek Greyman Ambidextrous AR-15 Charging Handle** $115.95

**Timber Creek Greyman Billet Dust Cover - AR15 Dust Cover** $33.95

**Timber Creek Greyman QD End Plate** $23.95

**Timber Creek Outdoors AR-15 Lower Parts Kit** $89.99

**Bcmgunfighter Ar-15 Enhanced Lower Parts Kit** $119.95

AR-15 Parts – Mil-Spec & Custom Rifle Components for Every Build

Whether you're building your first AR-15 or upgrading a trusted rifle, this is where it starts. At Mounts Plus, we carry a wide range of AR-15 parts — all mil-spec compatible, field-tested, and built to last. From full lower parts kits to small springs, safeties, and buffer systems, everything we stock is ready to drop in and perform.

🛠️ AR-15 Parts by Category

Browse top-quality rifle parts, organized by function and fit:

🔹 Lower Receiver Parts

Triggers, takedown pins, safety selectors, detents, springs, and grip screws

🔹 Upper Receiver Parts

Dust covers, charging handles, forward assists, and ejection port kits

🔹 Bolt & Gas System Parts

Gas rings, bolt catches, cam pins, gas keys, and firing pins

🔹 Recoil System Parts

Buffer springs, tubes, end plates, and spacers for tuning your recoil

🔹 Muzzle Devices

Compensators, flash hiders, thread protectors, and muzzle brakes

🔹 Enhanced & Ambidextrous Controls

Extended magazine releases, oversized trigger guards, ambi safeties

🔍 Why Choose Our AR-15 Parts?

We understand how important compatibility and performance are for AR builders. Every part we stock is selected for quality, fitment, and long-term reliability.

Mil-Spec Compatible: Fits all standard AR-15 lowers and uppers
Trusted Brands: ERGO, Timber Creek, Aim Sports, CMC Triggers, Aero Precision
USA-Made Components: Most parts are sourced from American defense-grade manufacturers
Ready to Ship: All parts in stock at our Florida warehouse
Tested for Fitment: We vet every part before it goes live

Whether you’re replacing worn internals or tricking out a new rifle, we’ve got what you need.

🔧 Build, Repair, or Upgrade with Confidence

Mounts Plus has supplied AR-15 builders for over two decades. We’ve helped thousands of customers:

Build rifles from scratch with complete lower kits
Replace trigger groups, springs, and pins for smoother operation
Add ambidextrous parts for left-handed shooters
Customize aesthetics with anodized billet upgrades
Upgrade recoil systems for tuning and comfort

No guesswork. No junk. Just parts that work.

🧠 AR-15 Compatibility Tips

All parts are compatible with mil-spec AR-15 platforms
Great for rifle, carbine, and pistol configurations
Pin sizes, threading, and tolerances follow U.S. military specs
Most parts are drop-in ready with basic tools

If you’re unsure about compatibility or need help choosing parts, our team is just a call away.

🛒 Order AR-15 Parts from Mounts Plus

From springs and detents to full parts kits and enhanced controls, we have everything you need to build, repair, or upgrade your rifle. We ship fast, stock only reliable brands, and back it with expert support. Whether you’re a weekend builder or a tactical pro, trust Mounts Plus to keep your AR-15 running right — every shot, every time.