Most Common Questions About AR 15 Parts

AR 15 Parts: Frequently Asked Questions

At the heart of every AR-15 enthusiast's journey is a quest for knowledge. Below, we've answered the most commonly asked questions about AR-15 parts to help guide you.

Q: Can I buy AR-15 parts online?
A: Yes, many AR-15 parts can be purchased online, including barrels, handguards, triggers, and more. However, there are some critical considerations:

  • Legality: While many parts are available for online purchase, specific components like the lower receiver (often considered the firearm's "controlled" part) may be subject to federal and state regulations. Ensure you are complying with both federal and local laws when purchasing.

  • FFL Transfer: Some parts, especially the lower receiver, require transfer through a Federal Firearms License (FFL) holder. This means that the item will be shipped to a local gun shop or FFL holder who will handle the necessary background checks and paperwork before releasing the part to you.

  • Know Your Supplier: Always buy from reputable dealers and suppliers. Read reviews, ask for recommendations, and ensure that parts meet quality and safety standards.

  • Shipping Restrictions: Some states or localities may have restrictions on shipping certain firearm components. Always check local regulations and consult the supplier's shipping policies.

  • Return Policies: Given the nature of firearm components, some vendors may have strict return policies. It's a good idea to understand these policies in case you need to return or exchange parts.

Always practice due diligence when purchasing firearm parts online. Stay informed about the laws, and when in doubt, consult a legal expert or a knowledgeable source in the firearm community.

Q: Can I legally modify or customize my AR-15? What are the restrictions?
A: While the federal government sets some guidelines, many regulations are state-specific. It's essential to consult local laws before making modifications. Common areas of concern include barrel length, stock type, and magazine capacity.

Q: What are the basic components of an AR-15?
A: The AR-15 consists of several key components, including the upper receiver, lower receiver, barrel, bolt carrier group, handguard, stock, and trigger assembly, among others. Each part plays a crucial role in the function and customization of the rifle.

Q: What's the difference between an AR-15 upper and lower receiver?
A: The upper receiver houses components like the bolt carrier group, barrel, and handguard. The lower receiver contains the trigger assembly, magazine well, and connects to the stock. These two parts are central to the AR-15's modular design.

Q: Are AR-15 parts interchangeable with AR-10 parts?
A: While the AR-15 and AR-10 platforms share a similar design, many parts are not interchangeable due to the AR-10's larger size (typically chambered in .308). Some components, like certain triggers or accessories, might be interchangeable, but critical parts like the upper and lower receivers, bolt carrier groups, and magazines are not.

Q: How do I install a free-floating handguard?
A: Installing a free-floating handguard can enhance your AR-15's accuracy. To do this:

  1. Ensure your firearm is unloaded and clear.
  2. Remove the existing handguard, front sight (if present), and barrel nut.
  3. Install the new barrel nut provided with your free-floating handguard.
  4. Slide the handguard over the barrel and onto the threads of the upper receiver.
  5. Secure the handguard using the provided screws or alignment system.
  6. Reassemble any other parts like gas blocks or front sights if needed.

It's advisable to refer to the manufacturer's instructions and consult online tutorials or professionals for guidance.

Q: What's the purpose of an adjustable gas block?
A: An adjustable gas block allows you to control the amount of gas redirected into the rifle's action. This can optimize the cycling of rounds, reduce recoil, and enhance the overall performance, especially if you're using various types of ammunition or have added suppressors.

Q: How do buffer weights and spring tensions affect AR-15 performance?
A: Buffer weights and spring tensions directly impact the cycling speed and recoil of the AR-15. A heavier buffer can slow down the bolt carrier group, reducing felt recoil but potentially affecting cycling reliability with lighter ammunition. Spring tension adjustments serve similar purposes, allowing for customization based on shooting preference and specific ammunition used.

Q: How can I upgrade my AR-15's trigger for a smoother pull?
A: Upgrading to an aftermarket trigger, like a single-stage or two-stage trigger, can offer a smoother and lighter pull. When choosing a trigger:

  1. Determine your preference: single-stage triggers have a consistent pull, while two-stage triggers have an initial slack followed by a definite break.
  2. Research reputable brands.
  3. Follow manufacturer instructions or consult a professional for installation.

Q: What type of bolt carrier group (BCG) should I choose for my AR-15 build?
A: The BCG is critical for the AR-15's function. Choices include full-auto/milspec BCGs, lightweight BCGs, and those with special coatings for easier cleaning or smoother operation. Your choice will depend on your rifle's intended use and personal preferences.

Q: Which magazines are best for my AR-15?
A: The best magazine depends on your needs. Consider factors like capacity, material (polymer or metal), brand reputation, and compatibility with specific calibers. Always check local laws regarding magazine capacity restrictions.

Q: What's the difference between a direct impingement system and a piston system?
A: Both systems use gas to cycle the AR-15, but they do so differently. Direct impingement sends gas directly back into the receiver to cycle the bolt, while a piston system uses that gas to drive a piston, which in turn cycles the bolt. Each system has its pros and cons related to cleanliness, recoil, and parts wear.

Q: How often should I replace certain parts, like the gas rings or extractor?
A: While AR-15s are robust, some parts wear out with use. Gas rings might need replacement after several thousand rounds, while extractors might last longer. Regular inspection and maintenance can help identify worn parts.

Q: What's the difference between mil-spec and commercial AR-15 parts?
A: Mil-spec (military specifications) parts adhere to strict standards set by the U.S. military. Commercial parts, while still functional, might have slight variances in size or material. It's crucial to ensure compatibility, especially with components like buffer tubes.

Q: How do I choose the right gas length system (pistol, carbine, mid-length, or rifle) for my AR-15?
A: The choice depends on your barrel length and intended use. Generally:

  • Pistol for barrels 7"-10"
  • Carbine for 10"-16"
  • Mid-length for 14"-18"
  • Rifle for 20"+

Your shooting preference and the type of ammunition can also influence the choice.

Q: What's the best type of finish or coating for AR-15 parts to resist corrosion?
A: Multiple coatings resist corrosion, with Cerakote, Nitride, and Hardcoat Anodizing being popular. The choice depends on your environment, usage, and aesthetic preference.

Q: Are there specific tools I should invest in for assembling or modifying my AR-15?
A: Definitely! Essential tools include an armorer's wrench, vise blocks, roll pin punches, and a torque wrench. A good quality bench vise is also invaluable for stable work.

Q: How can I troubleshoot cycling issues related to my AR-15's parts?
A: Cycling issues can arise from various components. Check the gas block alignment, ensure the gas tube is unobstructed, inspect bolt carrier group parts for wear, and ensure you're using the correct buffer weight for your setup.

Q: Which brands are considered top-tier for AR-15 components?
A: Brands like Daniel Defense, BCM (Bravo Company Manufacturing), Aero Precision, and Geissele are well-regarded for their quality AR-15 components, but there are many reputable manufacturers out there.

Q: What materials are best for AR-15 barrels in terms of longevity and accuracy?
A: Stainless steel offers superior accuracy, while chrome-moly steel (like 4140 or 4150) provides durability. Chrome lining can extend barrel life but may slightly affect accuracy.

Q: How do ambidextrous controls enhance the AR-15 platform?
A: Ambidextrous controls, like safety selectors or mag releases, cater to both left and right-handed shooters, allowing for more flexible weapon handling and faster operations in diverse scenarios.

Q: Are there benefits to using skeletonized parts on my AR-15?
A: Skeletonized parts reduce the overall weight of the AR-15, enhancing maneuverability. They also give the rifle a distinctive aesthetic, but may expose internal components to more dirt or debris.

Q: What considerations should I keep in mind if I want to use my AR-15 for hunting?
A: Ensure your AR-15 is chambered in a caliber suitable for your game. Also, consider factors like accuracy, weight for portability, and local hunting regulations regarding magazine capacity and rifle type.

Q: How does an AR-15's buffer weight impact its performance and feel?
A: Buffer weight affects the rifle's recoil and cycling speed. A heavier buffer can reduce felt recoil but might slow cycling. It's essential to balance buffer weight with your gas system length and ammunition type.

Q: Are there specific parts or brands recommended for competition shooting versus tactical usage?
A: Competition rifles often prioritize speed, with lightweight parts, adjustable triggers, and extended controls. Tactical builds might emphasize durability and reliability. Brands like Geissele or JP Enterprises offer competition-focused components, while BCM or Daniel Defense gear more towards tactical use.

Q: How do extended charging handles differ from standard ones, and why might I want one?
A: Extended charging handles provide a larger gripping surface, facilitating faster and more reliable charging, especially with optics mounted or when wearing gloves. They're beneficial for competitive shooters or those in tactical scenarios.

Q: What role does staking play in the assembly and security of certain AR-15 parts?
A: Staking involves creating an interference between screws and the material they're threaded into, preventing them from loosening due to vibration or recoil. Critical areas, like the gas key on a bolt carrier group, benefit from staking to ensure reliability.

As always, when working with or modifying firearms, safety should be the primary concern. Always refer to manufacturer's guidelines, consult professionals when in doubt, and follow all applicable laws and regulations.








Explore Black Rifle Depot's impressive selection of AR15 parts and AR15 parts kits, all available at discounted prices. Whether you want to enhance your current setup or embark on a new build, they offer a wide range of high-quality components to meet your needs. With their affordable prices, you can upgrade your AR15 without stretching your budget. Step into the world of Black Rifle Depot and discover how you can elevate your AR15 experience.