MY ARMALITE AR-10 A4 UPGRADE | AR-10A4CF

My Armalite AR-10A4CF was purchased back in 2012 in the months following the Sandy Hook massacre. That was a time when anything assault rifle related was impossible to buy. I also recognized that there was a good chance my home state would use the tragedy to impose more restrictions. I was not wrong. If I wanted to own an Armalite AR-10 I would need nothing short of a miracle. Fortunately that miracle presented itself in the form of Armalite’s former marketing director Arthur Steadman. Under Armalite’s previous ownership we had a fantastic working relationship from shortly after the launch of this site until Armalite sold to Strategic Arms Corp.  Anyhow I quick message to Arthur explaining my plight and he was on the case. A few days later I had an Armalite AR-10 A4 inbound, more specifically the AR-10A4CF. Naturally this was mostly great news.

ARMALITE AR-10 A4 Upgrade Ready

Unfortunately though beggars could not be choosers. I was not able to chose the AR-10 model I was getting. I had to settle on the AR-10A4FC. It was a demo booth rifle from SHOT Show. It was Armalite green and used Armalite magazines. I had hoped for a rifle that would accept the Magpul 308 PMAGS and anything other than green. This brings us to the point of this page, my AR-10 A4 Upgrade.

EASY DROP-IN ARMALITE AR-10 A4 UPGRADES

The other day we received an email from a reader “Michael”. Michael owns an Armalite DEF-10. The Armalite DEF-10 is an “A” series AR-10 that is nearly the same rifle as my AR-10A4CF. The major difference is the DEF-10 accepts the Magpul 308 PMAGS I mentioned previously while AR-10 uses the proprietary Armalite magazines. The DEF-10 also has a single stage trigger while my AR-10 AP4 has a two stage. Michael asked what can be done with his “Plane Jane” DEF-10. It occurred to me until now there was never a write up of my rifle on this site. Below is my rationale and parts choices for my AR-10 A4 Upgrades

AR-10 A4 UPGRADE – WHAT STAYED

When evaluating the AR-10A4 carbine as it shipped from Armalite it quickly became apparent that it is actually a very good rifle for it’s intended purposes and buyers. The rifle barrel and trigger stayed. The barrel and trigger combination for my purposes are sufficient. The rifle is not meant for long range competition. It is accurate enough for medium range hunting, tactical and defensive situations.

AR-10 A4 UPGRADE – WHAT’S REPLACED

Typically a firearms appearance doesn’t mean much to me. As I have stated many times on this site “Form must follow function”. I can appreciate a good looking weapon. I just wont base a hardware selection on appearances alone. That said I despise the green Armalite furniture especially the A2 handguard. Translation, rifle stock, pistol grip and handguard had to go. Beyond that I am left handed and  a huge proponent of the Battle Arms Development Ambidextrous Safeties. The factory safety was replaced.

MAGPUL ACS-L FEATURES

• Mounts on commercial-spec sized carbine receiver extension tube (not included) from manufacturers such as Bushmaster, DPMS, Olympic, and others (please see the note below)
• Sloping cheek weld provides a wide contact surface for user comfort
• Storage compartment in tail of stock with positive latching access door on right hand side
• Supplemental friction lock minimizes accuracy robbing wobble*
• Shielded release latch prevents snagging and accidental operation
• Premium chrome-silicon lock spring provides positive locking and long service life
• Replaceable 0.30″ Rubber Butt-Pad offers an anti-slip surface and increases impact protection
• Compatible with Magpul ASAP®, ASAP® QD, and other receiver-mount sling attachments
• Sling Mounts
  • Mid – Included reversible Sling Mount Kit – TYPE 3 fits up to 1.5″ push-button swivels (swivel not included)
  • Rear/Bottom – 1.00″ sling loop

MAGPUL MOE K2+ GRIP FEATURES

The 4×32 BROWE® Combat Optic (BCO) is a state-of-the-art optic that delivers the best-in-practice features of high-quality optical glass, high precision machining, and rugged military design with unique, next-in-practice features that puts the BROWE® Combat Optic (BCO) at the forefront of its class. The BCO offers customers a modern designed, internally-adjustable, combat optic with many unique features, such as Single Intuitive Control (SIC), Target Light Sensor Technology, field-programmable BCO Micro-controller, and a vibration sensor – all packaged in a rugged and versatile titanium housing.

Single Intuitive Control (SIC)

The operation is simple and intuitive.  The idea is revolutionary.  The system rests in the OFF position or SLEEP mode.  The first press of the SIC button puts the system into AUTOMATIC mode. In this mode, the LED automatically adjusts to the ambient light conditions using the Target Light Sensor Technology.  The second press of the button puts the system in MANUAL mode.  It starts at the brightest day setting and cycles through ten (10) day and three (3) night vision settings with every press of the SIC button.  Holding the SIC button for more than three (3) seconds puts the system back to SLEEP mode, conserving battery life. Hitting the button again puts it back into AUTOMATIC mode. Simple. Intuitive. Effective.

Target Light Sensor Technology

Through extensive R&D, we’ve discovered that mounting a sensor in the light path behind the objective lens magnifies the incoming light and provides greater accuracy of the target light levels.  In AUTOMATIC mode, this key feature allows the BCO reticle to be properly illuminated even when the user and target are in dissimilar light and avoids sensor errors caused from ambient light.  More importantly, as an operator is on the move, the BCO will continuously adjust automatically. For example, light levels can vary extremely from streets to dark alleys and buildings. In today’s urban warfare, when a nanosecond can make a difference, there’s no time to search for a poorly illuminated reticle or make manual illumination adjustments.

BCO Microcontroller

The BCO Microcontroller is the brain of the operating system. Its custom program reliably and easily controls all of the electronic features. Unique to the industry, the BCO microcontroller is capable of being re-flashed with alternative programs via a sealed flash port on the back of the battery housing. This port can also be used to attach accessories such as a momentary remote tape switch.

Vibration Motion Sensor

The vibration motion sensor conserves precious battery life by putting the electronics in SLEEP mode if motion is not detected after two hours. Additionally, if the SIC button is accidentally depressed in a carrying case or storage rack, the system automatically turns off after three (3) seconds. The BCO has an average battery usage life of 2000hrs. with a minimum of 775hrs. on max brightness.  In SLEEP mode, the battery will maintain the full 10 year life expectancy of a Surefire Lithium 123A battery.

Housing Designed to Accept Accessories

Versatility is at the forefront of the BCO housing design.  So you’ll find multiple areas for mounting “add-on” accessories. For starters, the OD of the eye-housing is a machined 30mm diameter surface with a 2mm groove for locking on dust covers or an assortment of other accessories.  Plus, two mounting bosses are placed on top of the housing for attaching additional accessories. On the objective end, we added a 42mm x 3mm OD groove and threaded the ID for added versatility for accessories, such as anti-reflection devices, dust covers, and/or laser filters.