When discussing the Mk 18 / CQBR program, we can divide the history and discussion in to two distinct categories: 1) The weapon system itself / upper receiver supplied and 2) the group of accessories deployed on said weapon systems (SOPMOD).

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Mk 18 Mod 0 / CQBR

The M4 carbine and M16 are not ideally suited for all missions, so it was proposed that the modularity of the M16 series would allow a user to replace the upper receiver of an existing weapon with one more suitable to the task. One of two proposed special mission receivers that were planned for inclusion into the SOPMOD Block II kit, the CQBR has taken off on its own. Like the proposed Special Purpose Receiver, the Close Quarters Battle Receiver has been more or less taken on by the Naval Surface Warfare Center, Crane Division (often referred to as NSWC-Crane or just "Crane") as its own project following the CQBR's removal from the SOPMOD program. Just as the Special Purpose Receiver morphed into the Special Purpose Rifle, and was type-classified as Mk 12 Mod 0/1, the complete CQBR-equipped carbine has been type-classified as the Mk 18 Mod 0.

The purpose of the CQBR remains to provide operators with a weapon of submachine gun size, but firing a rifle cartridge, for scenarios such as VIP protection, urban warfare, and other close quarters battle (CQB) situations. The CQBR is designed to provide improvement over previous AR-15/M16-type weapons in this category. The CQBR is usually issued as a complete weapon system, and not just an upper receiver. The CQBR was once only available to Naval Special Warfare units, but the Mk 18 Mod 0 has become general issue for Visit, Board, Search, and Seizure (VBSS) missions and, as of 2006, for NCIS agents deploying to active combat zones.[citation needed] The Mk 18 is also used by the Coast Guard's Tactical Law Enforcement Teams, Maritime Safety and Security Teams, and Maritime Security Response Team and the United States Navy's Explosive Ordnance Disposal (EOD) Operators.

Wikipedia has a good article with sources on the original CQBR/Mk 18 Mod 0 and its development.

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SOPMOD

The SOPMOD Program Management Office at NSWC Crane, IN, provides standardized, versatile weapons accessories to meet needs across SOF mission scenarios. These accessories increase operator survivability and lethality by enhanced weapon performance, target acquisition, signature suppression, and fire control.

The CQBR itself was originally part of the SOPMOD program as an accessory replacement upper receiver for the M4. However it was eventually separated out into its own project.

SOPMOD accessories for the M4/CQBR originally included things like the KAC RIS/RAS, SOPMOD stock, KAC M4QD suppressor, AN/PEQ-2 illuminator/laser, ECOS-N red dot, ACOG, etc

The SOPMOD program has gone through multiple minor and major evolutions throughout its lifetime. The most significant is commonly defined as "Block II" and included the introduction/replacement of accessories that met the updated needs of operators. The most visually significant "Block II" accessory is probably the replacement of the KAC rail/FSB with the  Daniel Defense RIS II free float rail with low-profile gas block. Other updates include things like the Surefire SOCOM sound suppressor, EOTech RDS (553/SU-231 & EXPS 3-0/SU-231a), LA-5/PEQ ATPIAL, etc

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Link to docs and photo albums

 Presentation on CQBR from Crane
 Operator's Manual for Mk 18 Mod 0
 SOPMOD Program Overview presentation from Crane
 Photo Album of Mk 18 Mod 0
 Photo Album of CQBR with SOPMOD Block II accessories

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Because of the long history of both the CQBR/Mk 18 and SOPMOD programs, it's common to find weapons with various mixed configurations in the field, all depending on what time and unit the weapon system belongs to. Below are a few examples with descriptions to illustrate this.


Example of a Mk 18 Mod 0 in as-issued configuration including: M16A1 surplus lower receiver, SOPMOD buttstock, KAC RIS, KAC M4QD flash hider, Aimpoint Comp M2 in Wilcox mount, LMT rear fixed sight, CQD rear sling plate.


NSW Operator CQBRs with original SOPMOD accessories including KAC M4QD sound suppressor and AN/PEQ-2 IR Illuminator/Laser.


Member of a Combat Camera team with a CQBR with KAC RAS and M4QD flash hider but with other updated accessories from the "Block II" SOPMOD kit including SU-231a (EOTech EXPS 3-0), EOTech G33 Magnifier, LA-5/PEQ ATPIAL, Insight WMX-200.


Good example of "early" CQBR with SOPMOD Block II accessories including SU-231 (EOTech 553) and SU-233 (Insight M3x weaponlight).


Example of a more "modern" CQBR with SOPMOD Block II accessories including the updated SU-231a (EOTech EXPS 3-0) and Insight WMX-200 weaponlight.


Many times certain configurations are common within certain branches/groups. Here a Marine Raider is seen with a CQBR with an AN/PEQ-16 (USMC issued vs. the LA-5/PEQ SOCOM issued ATPIAL) and KAC NT4 suppressor (vs. the current Surefire SOCOM suppressor).

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Building a clone

If you're interested in building a "clone" of a Mk 18 or CQBR equipped M4A1, here is a basic parts list to use as a guide and get you started. This list is not exhaustive and see the * note above regarding personalized accessories.

                       | Mk 18 Mod 0                      | M4A1 CQBR Block I                   | M4A1 CQBR Block II                                      
Lower Receiver         | Mil-spec forged A1               | Mil-spec forged A2                  | Mil-spec forged A2                                      
Stock                  | Gen 1 SOPMOD (Black)             | M4, CAR, SOPMOD, CTR & others       | M4, CAR, SOPMOD, CTR & others                            
Pistol Grip            | A1                               | A2, ERGO & others                   | A2, ERGO & others                                        
Rear Sling Plate       | CQD                              | CQD                                 | CQD                                                      
Upper Receiver         | Mil-spec forged M4 profile       | Mil-spec forged M4 profile          | Mil-spec forged M4 profile                              
Barrel                 | 10.3"                            | 10.3"                               | 10.3"                                                    
Rail                   | KAC RIS                          | KAC RAS                             | DD Mk18 RIS II (FDE)                                    
Rear BUIS              | LMT Fixed                        | LMT Fixed, MATECH, & others         | MATECH, KAC 300m, & others                              
Front Sight            | A2 FSB                           | A2 FSB                              | KAC 99051 BUIS (Taupe)                                  
Front Sling Attachment | FSB Sling Swivel                 | FSB Sling Swivel                    | CQD                                                      
Muzzle Device          | KAC M4QD                         | KAC M4QD                            | SureFire FH-556-RC                                      
Supressor              | None                             | KAC QDSS NT4                        | SureFire SOCOM556-RC (FDE)                              
LAM                    | None                             | PEQ-2                               | LA-5                                                    
Weaponlight            | SureFire M962                    | SureFire M952, M962                 | Insight M3X (Tan), Insight WMX200 (Bronze)              
Optic                  | Aimpoint Comp M2 in Wilcox Mount | Aimpoint Comp M2 in QRP Mount, ACOG | EOTech 553 (Tan), EOTech EXPS3-0 (Tan), ELCAN 1-4x (FDE)

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Link to previous threads

 Previous Mk 18 / CQBR Thread Part I
 Previous Mk 18 / CQBR Thread Part II

Well if I can offer any words of encouragement, I have zero regrets.  Being able to ogle it every night has been worth the price of admission.  I'm sure you'll feel the same way if you take the plunge!

And yes, the practice rounds are easy to get so no worries trying to hunt that stuff down.

And awesome looking rifle btw...it would make a great host.

I run an H2 with a factory Colt 10.3 without issue (suppressed and un-suppressed).

I used to run a DD 10.3 and could never get it to run reliably suppressed and un-suppressed. Mostly it was way over gassed and would cycle too fast with a can.

Also, the mailman just dropped off my Warden.

Yeah. I not only have never had a problem with either of my "commercial" DD 10.3s, but I can't even tell a difference between them and my .070 barrels - with or without a can.

I have tended to discover that most people complaining about or running into issues with commercial DD barrels were just simply not running a heavy enough buffer.

Don't really know what to think with that combination not yielding 100 percent results with the correct weight buffer.

Here's my point....since you decided to get snarky..If you're having problems with the rifle NOT locking the bolt to the rear with an H buffer, I would imagine the issue is going to be MAGNIFIED with the H3 IF you are experiencing a Short stroking issue.< THIS IS THE POINT I WAS TRYING TO MAKE
The flip side to this is that your rifle is cycling FAR too quickly for the bolt catch to engage, OR to pick up the next round - You would be severely overgassed and the H3 MIGHT be a "fix"  - If you TRULY are experiencing the malfunctions MORE when shooting suppressed, this may be the direction to go.

.EDIT - Removed comment... not worth it...

HEDP grenades require a tax stamp and wait for each one, IF you could even find one. Let alone find somewhere to blast it. You also have to comply with storage regulations and have your very own magazine, even if you only have one.

Unfortunately, the ATF, in all of their infinite wisdom, decided this year that chalk rounds as well as flare rounds, were now explosives, and fall under the same rules and regs as 40mm HEDP rounds. Meaning, a 200 dollar tax stamp for each chalk round. Makes about as much sense as them classifying M-18 smoke grenades as explosives, maybe even less so.

source

There are plenty of other sources on this as well, this was just one of the first ones I pulled up to substantiate that. Either way, though, it makes getting one even less attractive. I was planning on it, but knowing each pull of the trigger will cost more than 200 bucks, no thanks.

I can't figure out why tinypic keeps rotating my pictures. I don't know how to fix it.

Rotate them back?



Side note, I really like the way that Scout sits next to the Warden. Can't wait to pick up a FDE Warden.





 

I can't figure out how to rotate them on tinypic.

ETA: I can't wait to get my SOCOM out of jail.

Imgur for the win.



Tinypic used to randomly rotate some of my pics when I uploaded them too. Fuck em.

Waiting on one myself. Just turned in paperwork recently. Still want the Warden just cuz! :)



 

Oh god dammit. I guess that made that purchase a lot easier.... Seriously ATF,...wtf?

I should buy one purely out of spite.

Guess you're the only one that has had good service with them. Yes, they did move but that doesn't excuse them from shitty service. I would've understood delays but their complete lack of communication with me when I email/call dozens of times a day is inexcusable.

Got mine in tonight. From order to delivery in less than 22 hours..........no over night shipping either



Not CQBR, but I'll dig it out sometime and snag a pic.

Did you order the FDE one directly from SF?





I have the money for one now but I was going to buy another "stamp" on Friday... Have a lower sitting here that is lonely.
 

Nope. BCM. Their email notification came in at 12:20, by 12:25 my order was placed. I live less than 2 hours away from them.

Protecting the light was a benefit I didn't think of.

 

That was part of the selling point for me.

CQBR pics as promised. Not much room left with a DD barrel.

BCM Mk18 uppers are 11.5" so there not correct.

BCM sells 11.5 Mk18 uppers? That is teh retarded. Makes me think about turning my CQBR into a Close Quarters Troll Receiver (AKA CQTR)

No, they don't. They sell 11.5" uppers with Mk18 RIS II's.

The shortest barrel BCM has on their uppers is 11.5".

The whole rifle.. Because the rail on my current 10.3 sbr is not correct.

Don't care.

BCM 11.5" upper with DD RIS ll
My CQTR

That's a nice rifle.

This actually isn't true, people have been saying that based on how they read the letter (which is ambiguous).  If you head over to Grogs forums (and theres actually a thread on here in the DD forum), theres a thread where he talks about when the ATF confiscated some of this rounds (which they confiscated because there were obtained and then sold illegally).  He specifically talked to agents at the ATF, and was told the 40mm blue chalk is NOT banned in any form, and any that were confiscated were done so erroneously while they were collecting the flares that were sold illegally.  You can still buy blue death online from places like Clydes Armory all you want.

 

Sit through some of it, there is a bunch of CQBR goodness mixed in.

Thank you. It will get a correct length barrel at some point in the future. I need to pickup some suppressors first.

EDIT- Double Tap. Stupid iPad.

That is awesome! Thanks for sharing!

Thats Eric and I at 1:53

Thanks for clearing that up. I'll be looking into the sources you cited, my hopes lifted.

Dude I'm keeping that phrase around. Anytime somebody posts a random ass SBR in the CQBR thread, it's a CQTR.

So you can buy chalk rounds, but not flares or tear gas rounds?

Current 10.3" CQTR.. because MILSPEC gets annoyed.  And when the DD Mk18 shows up I'll throw a sopmod on it, BCM grip, extended trigger guard, and exps2-2 because I give zero fucks and prefer it. But I will try to get the Knights buis.

Aimpoints on sale at PSA,  the micro H1 is $399., ACO is $299

You have to add to cart and apply the code to see the sale price.

http://palmettostatearmory.com/black-friday-sales/bf-optics.html

Either you guys have extra large feet, or don't know how to use the view finder...........or get so damn focused on the CQTR that you can't see your toes in the pic.

It's the arf way.

Happy Thanksgiving.

Does the warden rattle on your FH/MB even when tightened down?

Nope.

Slowly we post less and less about the issues guns and more about non-clone stuff.

Well, I'm about to order mine, so I don't actually have it yet, but my SOCOM suppressor has the same mount and it doesn't "rattle", so I wouldn't imagine the warden would either.

Anyway, happy stuff your face day. In commemoration, I shall post some very old CQTR pics. Congratulations Milspec, you've coined a new term that will live on for eternity.

PSX_20151109_020408 by Alex Legore, on Flickr" />

Youtube Screenshot gun 3 by Alex Legore, on Flickr" />

I think you look really hard, the pixels on the left side of the image is me, and the pixels on the right seem to be a gun.

Excellent!

Give the ratchet one extra click and it won't rattle.

If you rotate the body back and forth a little while you tighten the collar will tighten it up a bit. It'll make it a little harder to release the collar though.

Happy Thanksgiving Mother Fuckers!

Ready to stuff my face like a fat fuck. Happy Turkey Day.

Post up some pics to get us on track!

 


Also, I wouldn't mind seeing some sling options other than CQD. Is the DD qd rail cup correct? I've got a couple of those in the parts container.










 

Soon Geissele will satisfy me with their trigger sale. Then SSA time. Still waiting on my stamp.