M16A1 BUILD LOG

tHE sTORY

Ente has always been a firearms enthusiast and interested in history, especially World War I, World War II and The Vietnam War. Ever since he first saw the iconic profile of the M16A1 he wanted one of his own.

Soldier of The 101st Airborne Division with his M16A1

Operation “Cook” September 8th 1967

Quang Ngai Province - Republic of Vietnam

President John F. Kennedy

Inspecting an M16 in the Oval Office April 19th 1963

Washington D.C. - United States

Why build one?

Well first of all, cost. An actual M16 can cost a pretty penny. Ente built his for less than $800 USD with new & reproduction parts.

(Tools not included in that price.)

Second, Ente has been an Automotive Mechanic, Electronic Service Technician, loves to work with his hands and learn new things.

How did he do it?

After some research it turns out the M16, official military designation: “Rifle, Caliber 5.56 mm, M16” was adapted from the ArmaLite AR-15 that was initially developed in 1956. That bit of information led into a rabbit hole on AR-Pattern rifles and how ArmaLite developed the AR Platform and Colt took over the military contract to produce M16s. ArmaLite sold the AR-15 design and the AR-15 trademark along with the ArmaLite AR-10 to Colt's Manufacturing Company in 1959. Colt started selling the semi-automatic version of the M16 rifle as the Colt AR-15 in 1964 to civillians, since then over 2 Million Colt AR-15s have been sold. After Colt's patents expired in 1977, other manufacturers began to copy the design of the Colt AR-15. The term "AR-15" is a Colt registered trademark which it uses only to refer to its line of semi-automatic rifles. Other manufacturers market generic AR-15s under other designations, but are frequently referred to as AR-15s. It is estimated over 22 million AR-15s have been sold.

Alright brief history lesson over.

So after learning that the M16 is in reality an AR-15 by a different name it was an exciting development for building his own. After some looking around and doing research on the weapons system it turns out that there are a few manufacturers that still make “Retro AR” parts. Most commonly today AR-15s have flat top receivers or M16A4/M4A1 style profiles. The integrated carry handle was replaced with a picatinny rail that allows for optional carry handle or most frequently the use of optics such as EOTech, LPVO, etc.

Ente started to do some research into where to find ‘A1’ style parts, the most important to the “accuracy” of the build was the upper receiver. He wanted an A1 upper receiver without the brass deflector with the ‘tear drop’ forward assist. There are A1 style uppers produced with brass deflectors often referred to as ‘C7’ upper receivers referencing the Canadian military’s adoption of the Colt/Armalite AR-15 platform, called the ‘C7 Rifle’ and features the A1 receiver with brass deflector.

After Maltz sent him a video of someone “Melting an M16 barrel after over 1,000 continuous rounds being fired” RangeTool commented on the posted video on how they contributed and it was a reproduction build, Thank goodness.

From that video Ente was referred to RangeTool who has been amazing to work with, RangeTool founded in 2010 is based out of Northern Minnesota and source all their materials locally in the USA. There was a mix-up with Ente’s order of the M16A1 upper receiver and they were prompt to respond and ship a replacement and paid for return shipping. Their customer service is impeccable!

After ordering the receiver he still needed the rest of the rifle, after some more searching around he found Linemount, a USA based company who offers retro firearm parts including M16. He sourced the handguard and pistol grip from them and their prices are modest and quality is top notch.

Ente knew the M16A1 came orignally with a 20 round magazine so he went to Duramag and ordered their C Products Defense 20 Round Magazine. Of course he got plenty of standard issue 30 round magazines for range days and training but wanted the original look with the 20 round mag for display purpose.

For the rest of the build he decided to go to Palmetto State Armory for the Lower receiver and parts kit. He chose a PSA Stealth Lower receiver, and Freedom Rifle 20” Barrel parts kit. The Freedom parts kit came with a flat top upper receiver and A2 handguards that were removed and he installed the barrel and gastube, charging handle and bolt carrier group onto the A1 receiver. From there it was time for assembly of the lower, and final assembly with furniture then the M16A1 reproduction was complete.

After it was completed he used headspace gauges to check the chamber clearance to ensure the rifle was safe to operate.

Accessories

After sourcing all the rifle build parts Ente wanted some accesories and after a little searching found a Surplus NOS(New Old Stock) M7 Bayonet to install on the barrel for display purposes. Ente also found a Ontario Knife Company leather scabbard for the bayonet since he likes leather holsters & sheaths over plastic. (He originally sourced an M8A1 Scabbard.) He went to Devil Dog Depot and purchased a USGI M16 Olive Drab Two-Point Rifle sling to use while carrying the rifle during training drills. (He originally got a Magpul MS1 Ranger Green sling but changed his mind for historical accuracy and display purposes.)

After a few months of research, careful planning, sourcing parts and tools, the build was finished.

Did we mention this is the first rifle Ente’s built?

Building a gun is a lot easier than building an Engine.

-Ente, February 18, 2025

A list of parts and tools used can be found below. For those who want to build their own M16A1.

Note: The A2 Freedom Rilfe Kit used is not a pencil barrel profile and it has an A2 Birdcage muzzle device, it is not 100% era correct for an M16A1. (The A1 has a lightweight barrel with a 1:12 inch twist, the A2 barrel used is a heavy barrel and is 1:7 inch twist.) With that in mind Ente was alright with these concessions he made as the barrel is a bit stronger and the A2 birdcage is a compensator by technicality (but is classified as a flash hider) so it will reduce muzzle rise.

At the end of the day it looks very close to period correct and the majority of people would not notice or care.

Thank you for reading if you made it this far!

-Ente & Maltz

Founders of Functional Reserve Militia

Built in America by American hands with American Made Parts.

ENTE’S M16A1

Parts:

  • Upper Receiver

    A1 Upper Receiver with Rear Sights, Forward Assist and Dust Cover

    Founded in 2010 residing in Northern Minnesota, Range Tool Company has been supplying OEMs and Brands across the country in the firearm industry.

    Product Made in USA

  • Lower Receiver

    Palmetto State Armory AR-15 Stealth Lower Receiver Stripped

    Since its inception, Palmetto State Armory has focused on providing the best quality AR-15 parts and accessories for the best price possible. Following year after year of exponential growth, Palmetto State Armory’s core principle remains the same, and our commitment to freedom before profit remains unwavering.

    Product Made in USA

  • M16A1 Retro Triangular Handguard Set

    Handguard

    M16A1 Retro Triangular Handguard Set

    Linemount is dedicated to providing hard-to-find, high-quality firearm parts and accessories for responsible shooters and enthusiasts.

    United States based company

    Product Made in Taiwain

  • M16A1-Style Pistol Grip

    Pistol Grip

    M16A1-Style Pistol Grip

    Linemount is dedicated to providing hard-to-find, high-quality firearm parts and accessories for responsible shooters and enthusiasts.

    United States based company

    Product Made in Taiwain

  • C Products Defense 20 Round Magazine

    Magazine

    C Products Defense 20 Round Magazine

    The DURAMAG® story begins with the creation of C Products Defense, Inc. established in Bradenton, Florida in 2011. The company started with the creation of new magazine designs and fresh production techniques. CPD’s work continued with the purchase of all new equipment, tooling, and molds.

    Product Made in USA

  • PSA 20" Freedom Rifle Kit

    Parts Kit

    PSA 20" Rifle Length 5.56 NATO 1/7 Nitride A2 Freedom Rifle Kit

    Since its inception, Palmetto State Armory has focused on providing the best quality AR-15 parts and accessories for the best price possible. Following year after year of exponential growth, Palmetto State Armory’s core principle remains the same, and our commitment to freedom before profit remains unwavering.

    Product Made in USA

  • USGI M16 Olive Drab Two-Point Rifle Sling

    Sling

    USGI M16 Olive Drab Two-Point Rifle Sling


    Devil Dog Depot provides high-quality Marine Corps products and outstanding service to our brothers and sisters across the nation and around the world. Their Mission is to provide our customers with an excellent selection of USMC products, fast shipping, competitive prices and our signature 5-Star customer service.


    Product Made in USA

  • M7 Bayonet US Issue

    Bayonet

    M7 Bayonet

    The M7 bayonet is a bayonet that was used by the U.S. military for the M16 rifle. It can be used as a fighting knife and utility tool. It was introduced in 1964, when the M16 rifle entered service during the Vietnam War.

    Ontario Knife Company has produced knives for many decades and all have seen combat with U.S. armed forces. Needless to say, these veteran blades are not in the business of giving quarter.

    Product Made in USA

  • Ontario Trench Knife Belt Sheath

    Bayonet Sheath

    Ontario Trench Knife Belt Sheath

    Ontario Knife Company has produced knives for many decades and all have seen combat with U.S. armed forces. Needless to say, these veteran blades are not in the business of giving quarter.

    Product Made in USA

Recommended Tools:

  • Midwest Industries Upper Reciever Rod

    Upper Reciever Rod

    Midwest Industries Upper Reciever Rod

    Midwest Industries was founded in 2003 by two partners in the precision machining industry, united by a lifelong belief in American-made products, American values, and the second amendment. Since the company was founded, their goal has been to provide high-quality parts with innovative features at a price point that is attractive for all levels of income.

    Product Made in USA

  • Midwest Industries Handguard Removal Tool

    Handguard Tool

    Midwest Industries Handguard Removal Tool

    Midwest Industries was founded in 2003 by two partners in the precision machining industry, united by a lifelong belief in American-made products, American values, and the second amendment. Since the company was founded, their goal has been to provide high-quality parts with innovative features at a price point that is attractive for all levels of income.

    Product Made in USA

  • Pro Mag Lower Receiver Magazine Well Vise Block

    Vise Block

    Pro Mag Lower Receiver Magazine Well Vise Block

    Dedicated to only turning out superior products for dependable performance has held true since their conception. In fact, ProMag is one of the leading manufacturers of handgun magazines in the world.

    Product Made in USA

  • Magpul Armorer's Wrench

    Armorer's Wrench

    Magpul Armorer's Wrench

    Our name comes from our original product, the Magpul, which aids in the reloading of mags during combat. Founded by a Marine in 1999.

    Product Made in USA

  • W Wiregear Pin Punch Set

    Pin Punch Set

    W Wiregear Pin Punch Set

    W Wiregear is a brand that makes tools for installing and adjusting handgun sights. Their products include sight tools and pin punch sets.

    Product Made in USA

  • Wheeler Engineering Pin Starter Punch Set

    Pin Starter Punch Set

    Wheeler Engineering Pin Starter Punch Set

    For over two decades, Wheeler has consistently provided rugged, high-quality tools and accessories that the pros use, to build and maintain firearms. Each product reflects our history of innovation, ensuring that our tools will last a lifetime. We are known for our unwavering commitment to providing tools that are made to build and built to last.

    Product Made in USA

  • WHLLING Center Punch Set

    Center Punch Set

    WHLLING Center Punch Set

    Established in 2016, WHILLING have done offline business operation for many years, their company is dedicated to hand tools, crafts & equipment.

    Product Made in China

  • Takedown Pin Install Tool

    Takedown Pin Install Tool

    WHILLING Takedown Pin Install Tool

    Established in 2016, WHILLING have done offline business operation for many years, their company is dedicated to hand tools, crafts & equipment.


    Product Made in China

  • Forster Headspace Gauges

    Headspace Gauges

    Forster Products 5.56 Headspace Gauges

    Forster Products has been making some of the world's most popular precision reloading and gunsmithing tools for over 80 years.

    Product Made in USA

  • Eklind Tool 3/16" Hex T-Handle Wrench

    Hex Key

    Eklind Tool 3/16" Hex T-Handle Wrench

    Founded in 1923, Eklind Tool Company is your complete source for the highest quality, professional grade tools.

    Product Made in USA

  • Snap Ring Pliers

    Snap Ring Pliers

    SK Snap Ring Pliers

    An american brand, since 1914. Innovating for American Professionals since day one. High quality precision-crafted tools. We continue or commitment to quality innovation for the world's toughest professionals. Tools that work as hard as you do.

    Product Made in USA

  • Building/Cleaning Mat

    Building/Cleaning Mat

    2F22E Building/Cleaning Mat

    The pattern on the work cleaning mat is very clear, including complex disassembly steps and details. Experience Ultimate Convenience! This cleaning pad is made from eco-friendly, resilient materials, ensuring a scratch-free, durable surface for safe and effective maintenance.

    Product Made in China

  • AR-15 Rifle Builder's Manual

    Rifle Builder's Manual

    AR-15 Rifle Builder's Manual

    Rob spent his professional writing career as the editor of several national automotive, off-road and outdoor magazines (including Mustang Monthly, Mustang Enthusiast, Jp, J Rations and Heartland USA), and as a freelance writer, columnist (Guns & Ammo, Petersen's Hunting and Outdoor Life) and photographer.

    Product Made in USA

Extras:

  • Pistol Grip Plug

    Pistol Grip Plug

    MLLL Pistol Grip Plug

    Plug has special cavity for storing CR2023 battery and small Allen wrench. You can also store larger battery for your electronic optics, or any smaller object you will need to have quickly accessible. This plug will also prevent dirt from entering the grip. This plug should fit snugly any fits standard A1 or A2 grip. The plug prevents debris from lodging in the cavity of the grip and functions as a shock absorbing pad to protect the when setting the down on hard surfaces.

    Product Made in USA

  • Threadlocker

    Threadlocker

    Permatex Orange High Strength Removable Threadlocker

    Orange Thread locker can be removed with hand tools and does not require heating to achieve removal

    Permatex Orange Thread locker ensures that pieces will not loosen or back out over time. 3X the strength of Blue Thread locker, Ideal for High Vibration Applications. Use for: Automobiles, Motorcycles, Heavy Equipment, Marine and Industrial Applications

    Product Made in USA

  • Adhesive Ceramic Cement

    Adhesive Ceramic Cement

    Rocksett

    Popular for muzzle brakes / recoil compensators and suppressors, Keeps assemblies from vibrating loose. Electrical insulation - for both A.C. and D.C. up to 20 Radio MHz. Non-Toxic - odorless - non-flammable - Long Shelf life. Stands with oil, fuels, acids and alkalis. No Mixing or priming required.

    Product Made in USA

  • Military Speed Loader Stripper Clips

    Speed Loaders

    Military Speed Loader Stripper Clips

    Devil Dog Depot provides high-quality Marine Corps products and outstanding service to our brothers and sisters across the nation and around the world. Their Mission is to provide our customers with an excellent selection of USMC products, fast shipping, competitive prices and our signature 5-Star customer service.


    Product Made in USA

  • Military M16 Butt Stock Cleaning Kit

    Cleaning Kit

    Military M16 Butt Stock Cleaning Kit

    Devil Dog Depot provides high-quality Marine Corps products and outstanding service to our brothers and sisters across the nation and around the world. Their Mission is to provide our customers with an excellent selection of USMC products, fast shipping, competitive prices and our signature 5-Star customer service.


    Product Made in USA

  • 16″ Gas Tube Cleaners for M16/M4

    Gas Tube Cleaners

    16″ Gas Tube Cleaners for M16/M4

    Devil Dog Depot provides high-quality Marine Corps products and outstanding service to our brothers and sisters across the nation and around the world. Their Mission is to provide our customers with an excellent selection of USMC products, fast shipping, competitive prices and our signature 5-Star customer service.


    Product Made in USA


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