The Civilian Defensive Rifle – Part 2: The Build

in Authors, Build an AR, GA Guides, Matt Kartozian

Updated: June 17, 2023 BY Matt Kartozian

Estimated reading time: 14 minutes

M-81 Cerakote in the Arizona desert. — The CDR blends well with the Arizona desert with M-81 Arid Cerakote by Pro 2 Customs.

Read Part 1 HERE: The Civilian Defensive Rifle, Part 1: New Gas Length

Law Tactical Folding Stock Adapter on the CDR
JP Silent Captured Spring In the CDR
Muzzle Adapter and Light For the CDR
Handguard on the CDR
Optics Options for the CDR
Grip and Stock
The M&M’s Incident
Magpul Finishing Touches
M-81 Arid Cerakote – Pro 2 Customs
Ammo Testing with the CDR
Final Thoughts on the CDR

Law Tactical Folding Stock Adapter on the CDR

Law Tactical folding adapter in FDE. — Law Tactical folding stock adapter on the CDR.

I wanted the Civilian Defensive Rifle to be small for transport and a LAW Tactical folding stock adapter was just the ticket to achieve that. The Gen 3 adapter works well and is simple to install. It’s made of 4140 steel and coated with an Ionbond DLC finish, so it is durable as hell. If it loosens or gets sloppy over time a set screw allows you to tighten everything up again for a solid lockup. The adapter also has a QD swivel pocket built to make mounting your sling easy. With the can removed and with the stock folded the rifle is only 22.5 inches long.

The Law Tactical folding adapter is great when you need a short rifle for transport. — With the Law Tactical adapter folded the CDR is only 26 inches.

JP Silent Captured Spring In the CDR

As mentioned previously, I was using the JP Silent Captured Spring system instead of a standard spring and buffer. The LAW Tactical folder requires the use of a small plug in the back of the BCG since the adapter adds length to the buffer tube. JP makes a version of their SCS with their own plug specifically designed for use with the LAW folder. The SCS makes your gun quiet and you won’t hear the annoying “sproinnngggg” sound of the spring and buffer vibrating inside the buffer tube while under recoil.

The JP SCS keeps the CDR quiet. — JP Enterprises Silent Captured Spring and FMOS BCG used in the CDR.

The SCS is super tunable as well. Using a variety of spring weights and steel or tungsten weights on the guide rod you can tune your SCS to act like a super lightweight buffer or up to H2. I ended up running the lightest spring and zero weights.

Muzzle Adapter and Light For the CDR

A Surefire SOCOM muzzle brake was screwed onto the barrel to allow mounting of the SOCOM556 RC2 can. Some people would prefer the Warcomp flash hider adapters for a defensive rifle; both reduce muzzle flash a lot more than the muzzle break. I prefer the muzzle break as it reduces recoil the most, and if I am in a fight and need to remove the can I have much bigger problems than muzzle flash. With the can attached, the muzzle flash is tiny and not an issue, even at night.

Stay quiet and have a bright light, Tw primary features of the Civilian Defensive Rifle. — The Business end of the CDR. Surefire Socom556 suppressor and Scoutlight Pro.

A Surefire Duel Fuel Scout Light Pro (model M640DFTN-Pro) was added for nighttime use and attached to the rail via M-Lok. I did not need a fancy switch for the light. Where I have it mounted to the left side of the handguard I can easily engage the tailcap switch with my left thumb when mounting the rifle. For those using IR lights or lasers, the rail can get crowded and the fancy switches help.

CDR with Law Tactical folder open. — CDR with Law Tactical folding stock adapter in the open position.

The light puts out 1500 lumens/16000 candela with the dual fuel 6v power cell and 1200 with CR123A batteries. It is plenty bright to see targets at 100 yards. The DF power cell gives you a runtime of 1.5 hours or 1.25 hours with CR123s. It is also light at only 5.5 ounces. There are fancier lights out there but I prefer the simplicity and reliability of the Surefire.

Handguard on the CDR

I really like the Midwest Industries Ultralight handguard on my competition rifle but needed a shorter version for the CDR. I used a 10.5-inch version of their lightweight handguard. The difference between lightweight and ultra-lightweight is the barrel nut and screws. ULW uses titanium while the LW uses steel and aluminum. The ULW weighs 6.3 oz in the 10.5-inch model while the LW is 7.6 oz. If you have a LW you can buy the titanium nut and screws later to make it ULW. The rail has a ton of M-lok slots and there are small cuts and scallops all over it to shed every gram possible. There are also 2 QD sling pockets built into each side of the rail.

Use the Titanium barrel nut to save another 1.3 oz. — The CDR uses Midwest Industries Lightweight 10.5 handguard weighs only 7.6 oz including the barrel nut.

Optics Options for the CDR

I ran a lot of different optics on the Civilian Defensive Rifle during testing including Nightforce ATACR 1-8, Nightforce NX8 2-20, Leupold Mk5 HD 3-18, and an Aimpoint H-2 6 MOA. The 1-8 was great for 3 gun style matches, and the 2-20 and 3-18 were used for medium-range shooting out to 800 yards. As this is a defensive rifle and unlikely to be used past 50 yards I settled on my favorite red dot for everyday use. The Aimpoint H2 6MOA.

Many optics were tested with the CDR. — The CDR with Nightforce ATACR 1-8 with an offset Trijicon SRO red dot in a Scalarworks Leap/09 with sidekick mount.

I previously reviewed the H2 6MOA but here are the highlights. It’s an Aimpoint so you can kick the crap out of and it will still work. It has the crispest roundest dot of any modern red dot sight and whats’ more, it’s small and light. The big 6-minute dot is outstanding inside 50 yards and very useable to 300 yards and beyond. It does not cover the target at longer ranges despite what internet people may tell you (see the review for why). Paired with a Scalarworks Leap 01mount it weighs just over 5 oz. When combined with a Trijicon Mag C 3x magnifier it becomes easy to see and engage a full IPSC to 450+ yards. It’s a fast, light, simple, and reliable optic setup.

The CDR with long glass for long range shooting. — The CDR during a PRS match wearing a Nightforce NX-8 2.5-20 with MIL XT reticle.

Grip and Stock

The final parts to finish the Civilian Defensive Rifle all came from Magpul. The K2XL grip is about 25% bigger than the standard K2; beware this thing is girthy! K2 grips have a more vertical angle that I like and as I have big hands the XL version is even better. A UBR Gen2 stock was also added. The buffer tube is integrated with the stock so you don’t need to buy a tube. It comes with a spacer if you are running a carbine buffer or you can leave the spacer out to run an A5 buffer or when using with a large frame AR10/SR25 rifle. The tube has 8 positions of adjustability to fit just about anyone.

The CDR in action at a medium range AR match. — Magpul UBR Gen2 stock gives you a great cheekweld.

The UBR is something of a hybrid stock combining the best of adjustable-length carbine stocks with the rigidity and consistent cheek weld of a rifle stock. It is 5 oz lighter than the original UBR as well. There are 2 QD sling pockets and a lot of storage.

The M&M’s Incident

The UBR Gen2 stock will fit 49 M&M's. — Magpul UBR Gen2 stock with 49 M&M’s

I have seen a lot of people over the years joke about storing M&M’s in their Magpul parts. Up until now though, I never found a definitive answer on how many fit. Well this is GunsAmerica and guns and candy are serious business so for you guys, the readers I found out. The UBR Gen2 will hold 49 standard (non-peanut M&M’s) and the K2XL will hold 54 for a grand total of 103. Reeces Pieces gave similar results give or take 2.

Melted chocolate in the stock makes a mess. — They melt in your mouth and in your stock.

WARNING:

M&M’s, Reeces Pieces, and all chocolate-based candies should never be stored in your Magpul grip or stock during summer matches. Despite the candy coating, they will melt. Stick with something like Pez and save the chocolate candy for wintertime. Both my stock and grip became a melted mess of chocolate and broken shells. Once home in the air conditioning, they solidified into solid lumps. The grip had to be removed and the stock had to be completely disassembled to chisel out the big chunks. A lot of small remnants remained and lots of hot water and elbow grease were required to totally eradicate the chocolate. 1 star, do not recommend.

Prying chocolate out of the CDR stock. — Chiseling out M&M’s after the melted chocolate cooled.

Magpul Finishing Touches

For stability and shooting prone, I used the Magpul bipod with the ARMS 17s head with the Rail Grabber adapter. The Magpul bipod is light yet durable with a lot of vertical adjustment. The Rail Grabber lets you quickly attach or detach the bipod from your rifle with a twist of a knob. It also attaches to both Picatinny and ARCA rails giving you a ton of versatility.

PMAG was the only choice for he CDR. — PMAGs, because they work and are inexpensive.

Lastly, the Civilian Defensive Rifle was fitted with the king of magazines, the PMAG. I like the windowed 30-round versions as I can see how many rounds I have left in the mag. PMAGs are cheap, reliable, and super durable. Why use anything else?

M-81 Arid Cerakote – Pro 2 Customs

Once the Civilian Defensive Rifle was built and finished, the upper, lower, and handguard went over the Pro 2 Customs to get a little flair and style. I like desert camo styles and I live in the desert so it works well here too. Bryan at Pro 2 did an amazing job applying M-81 Arid camo to the Civilian Defensive Rifle using Cerakote. M-81 is the old 80s woodland camo pattern used in the US and Arid is the desert version. As seen in the photos the M-81 Arid blends in nicely with the Arizona desert. They do some cool and crazy coatings (like Miami Tiger Stripe) so give them a call if you want a cool Cerakote job for your pistol or rifle.

The CDR with custom Cerakote. — Detail view of the side charger handle and M-81 Arid Cerakote by Pro 2 Customs.

Ammo Testing with the CDR

My ammunition pick for using the CDR is IMI Razercore 77gr OTM. This is IMI’s copy of Mk262 by Black Hills. It is often easier to find and about 25 cents less per round while performing at 95% of the Black Hills in terms of velocity and accuracy. Mk 262 aka 77gr OTM uses a Sierra Match King 77gr bullet and gets speeds around 2700 fps in an 18-inch barrel, 2400 fps in the 11.5 CPO. I like it because the Sierra Match King bullet design dumps a ton of energy into the target in a very short distance. It is fast and has a proven track record when shooting people in short-barreled rifles.

A great group for a fighting rifle. — 1.13 MOA 5 shot group at 200 yards with Razorcore 77gr OTM.

I tested a variety of ammo in the Civilian Defensive Rifle using 55, 75, and 77gr projectiles in both handloads and factory ammo. Hornady 55gr produced groups around 1.4 MOA and the Razorcore 77gr about 1.1 MOA at 100 yards with the suppressor. With the can removed the Razorcore was under 1 MOA at 100 yards.

Final Thoughts on the CDR

As always, part of my testing process included shooting the rifle in competitions. I brought it to Multigun, medium-range AR matches (400 yards), long-range “accurized” style AR matches (700 yards), and even a PRS match. It held its own in the mid-pack of the multi-gun and AR matches, and while outclassed in PRS it did make some tough hits on small targets far away.

The CDR can easily hit targets past 300 yards with a red dot. — Engaging 300-yard targets from a tank trap with an Aimpoint H-2 red dot and Trijicon 3x magnifier.

Hitting a man-sized target out to 400 yards is easy like Sunday morning for the CDR, and 400 yards is a lot farther away than it or I will likely face in a defensive scenario. It is extremely reliable, and exactly what I want in a defensive rifle.