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

Second from Bottom is airsoft.

Any further info on this pic? I'm curious because of the .40 Glock (FDE mag extension), the Ranger Green MBAV/MAP, and Mk18.   I was told some Glocks in 9 are being issued in Ranger Regiment, mostly for use with suppressors.

 










 

Here's some more from the same set of images - title of the set is "U.S. Army Special Operations Command 2012 Capabilities Exercise, April 20."

They are SFARTAETC (Special Forces Advanced Reconnaissance, Target Analysis, and Exploitation Techniques Course) instructors at Fort Bragg giving a demonstration during part of 2012's CAPEX.

Meant to post these with my last group. Not sure what happened there.  

Just rattle can that lower, nothing looks more clone-like than a crappy paint job, Oh and I got a NT4 for you.

This isn't a glock thread, but thanks again for the derailing. This is a Technical Forum.  Keep it Technical, please - Old_Painless

MARSOC CQBR

More MARSOC Marines with Mk18s.

Here are mine. Only non-Colt parts on the two rifles (excepting the obvious) are the Noveske stripped lower and LMT bolt catch on the Mod 0. Hopefully I will get my QDSS NT4 in the next couple of months. I need to hit the Mod 0 Block I CQBR clone with some paint when the weather improves.




ETA: The Mod 0 Block I CQBR(?) has a RAS not the RIS.

If anyone has a lead on a used nt4 flash hider or one at a decent price, shoot me an email or pm.

Tagscribbage......................let's not get this one fucked up too.

The only grip on Mod0's were A1, they were surplus M16A1 lowers and we had no lasers of any kind, the Mod0 was used on onboard ship for VBSS.

Murphy and Axe we not using Mk18's, they used CQBR M4A1's, which of course would have A2 grips and used for laser designators. I know it's splitting hairs but the CBQR and Mod0 were used by entirely different personnel for different missions.

William

My Old School Mod 0.





It's a 10.5 LMT barrel, No happy switch and a magpul trigger guard but other than that it's all spec., including the Knights RIS.


 

This thread is awesome!!! Thank you for making a new one and lets keep this one as close to spec as possible

Let's keep this thread clone... and civil.

(Note: The non-rotating pins are a departure from a CQBR clone and will be replaced shortly)

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I've got to rebuild my M18/CQBR in a week or so, I plan on taking a picture similar to that one.

PUT IT TOGETHER!!! If you needs tools I'm your man.

William in Titusville

Anyone SBR a 6920 SOCOM for the M4A1 markings? Where did you do your engravings? I'm tearing down my non-spec Block II CQBR and want to try and do a super-spec clone when money frees itself up. Would probably pair it with a proper 14.5 PR upper or B2 upper as well someday.

Thanks for the offer of help and tools William, but it is together (the photo above it is the completed weapon)... and is a nail-driver. With the exception of the non-rotating pins it is built to spec with all Colt parts, H2 buffer, extractor upgrade, etc. made it as close as I could get it. Couldn't bring myself to run the KAC vert grip though so I put on a KAC handstop and use that as a small vert grip.

anyone have a good left side view of the rollmark on a Gov't issue M4A1 CQBR?   also, would the right side of said receiver have the selector markings?     Thanks guys.

Hey William, thanks for the info, and good point. Is there any functional difference between the two besides the lowers they were put on? Seems like Mod 0s and CQBR block 1s were almost exactly the same parts?

Nope, and yes. I'm pretty sure Crane built the CQBR as well though Augee would be the go to guy for that info. The Mod0 and Mk12 were born of the same parts hence the A1 lowers that were destined for scrap. I've never seen a CQBR in person but handled many a Mod0 on the Erie, CG-70.

The question pertaining to rhs side of a CQBR would be yes they have SAFE SEMI AUTO on both sides, as all M16A2 through M4A1 have. One thing I have noticed though is that they are mostly low serial range, W3XXXXX-W4XXXXX. Perhaps they (and the Block II) are from the original SOPMOD program?

William

Thanks William.      more programming in the works.

 

I believe the Ergo grip was also used on Mk18 mod 0s, but I'm not sure.  It is certainly an acceptable part as it is commonly used and easily changed out by the end user.

 

I think they both used the RIS, bound to be a mix of them somewhere though.

William

They look the same to me.....  But hey....learn something new everyday.  

Anyone have leads on a CQD Sling Mount ?

I have an aac can not an nt4

MK18 Mod 0 is still my fav build of all time.

Keep the pics coming.

Both appear to be in-stock on CQD's website.

DSGArms

That's actually a M962, not a M961, as it has the ARMS quick detach feature.  The pic of the Navy arms room one also has a Surefire SW02 tail cap.

Here's my humble contribution, a Mod0 upper but more of a CQBR lower. I'm just about finished with my SAM-R build, finally. Once it's GTG I'll post family pics with the Block II as well.

William

IIRC didn't LMT also make some of the uppers for the Mod 0's in 10.5" format?

Ok.  Please someone help me understand this...comparing the base rifles (no accessories) what is the difference between a mod0 and a CQBR block 1?  Is it the receiver?  Auto vs burst?  A2 hider vs nt4?  I'm not trying to be an ass....i reallly want to know.  I have wanting to clone axes rifle for some time now.

 












 

Pretty much this ^ The Mod0 is afaik only used by the Navy onboard ship, the CQBR is seen with a host of accessories which we did not have when using the Mod0.
A flashlight (M962) and a sling is all I was ever given.

William

Ok...got it.  Thanks for the clairification.  Makes sense now why I see Luttrel and Dietz with M4's vs the 10.3".

Thats a lot of muzzle flash.

WTH I go off the grid for a weekend and come back to fine my favorite thread nuked!

So who went full retard?


Now that I vented...
What is the "official" threshold for clone worthyness?

I trashed my Wilcox mount cuz I thought it sucked and swapped for a Larue. I didn't want to spend $300 on a 962 light and use a Streamlight. It's a lot brighter than my buddies 961. Which comes in handy when lighting up a distant tree line looking for coyotes. The problem is i use my Mod 0 clone, it's not a "safe queen" or just a "range toy".

My muzzle device is wrong also. I use a YHM can as I've not felt like spending $1500 vs $500 for a can because it has dimples and is "more" correct. The old thread did not step on me because I had the basics.

Where does the new thread stand? Does it have to be 100%, working towards 100%...?

Check • Barrel: 10.3 Colt Government profile with .70 gas port
   Colt 6921 upper chopped to 10.5"
Check • Rail: Knights Armament M4 RAS  
Nope • Muzzle Device: Knights Armament NT4 Flash Hider
         Why is the A2 not listed? Well I run a YHM...
Check • Front Sight: A2 FSP    
Check • Rear Sight: LMT  
Check • Optic: Aimpoint CompM2
Nope • Optic Mount: Wilcox      
        I thought the Wilcox sucked... Tired of using locktight, switched to Larue
Check • Stock: LMT SOPMOD Gen 1 Black
        Not a B5 knockoff
Nope • Grip: A1
        I have A1 and A2 grips but prefer the MOE
Nope • Light: Surefire M952
       Not spending $300 on a M962 running a Streamlight
Nope • Supressor: Knights Armament NT4
       I saved over $1000 and use a YHM not an small amount to me...

Yeah I run the wrong trigger guard also....

How it sits now...


And this was purely a dress up pic


Dang it had an ASAP on it...