Purpose
The CQRR build was born of pandemic boredom and later practical need. The goal was a general purpose carbine with sub 2 MOA capability to 400 yards, non NFA, “Recce” style use concept. Carbine usable for close range (less than 100 yards) but also capable of accurate target acquisition at distance (400+ yards). Also, a lower receiver test bed for build with Forward Control Design components.
Attachment 63010
Upper receiver
The original “recce” concept used a match grade stainless steel barrel to achieve the mission driven accuracy standards. A SS barrel with carbine gas system was the only barrel of the time that would meet the need. Today, there are numerous barrel options. Some chrome lined barrels offer excellent accuracy. Melonite or QPQ barrels now offer a bridge between the reliability of chrome lined barrels and the accuracy of stainless steel match barrels.
I considered many barrels before favoring two. I didn’t want a SBR or pinned & welded barrel, so I limited my choices to 16” barrels. I also wanted a mid length gas system. The Noveske 16” Chrome Lined, hammer forged, mid weight profile barrel and the Ballistic Advantage 16” Hanson profile 556 melonite barrel. Both of these barrels offer a better profile than the Gov profile, with better weight distribution and harmonics. Both barrels are known for being very accurate, especially with match grade ammunition such as Black Hills Mk 262. Both companies also offer a pinned gas block for reliable operation.
The Noveske barrel is possibly more accurate than the BA Hanson barrel. The Noveske barrel likely has more longevity than the BA barrel, being hammer forged. The BA barrel however offered acceptable accuracy and longevity at less than half the cost of the Noveske barrel.
I decided on the 16” BA Hanson barrel for this project. Part of this decision is the capability of the primary operator (me) being a 2.5 MOA capable shooter out to 300 yards. I’m not entirely sold on melonite as a substitute for chrome lining when it comes to longevity, but it seemed like a good compromise for this build.
I used a Vltor MUR upper for its tighter tolerances and potential improved accuracy. The barrel and receiver fit together tightly, without any wiggle.
Of course a free floated hand guard for improved accuracy, while offering the flexibility of various support hand positions and providing a secure platform for mounting a future IR laser was a requirement of this build. I chose the LaRue Tactical MLOK hand guard for its balance of weight, strength/ruggedness, and because…Texas.
Optic
In the original military “recce” rifle, a common optic used was a variable 2.5x10. I wanted something more usable at short range (under 25 yards), and the modern LPVO seemed the way to go. I made conscious decision throughout the build to sacrifice some accuracy potential for more practical use. I chose the Nightforce NX8 1x8 FFP for its 1X usability and its FFP magnification when used at distances beyond 100 yards. The NX8 is also lighter (about 17oz before mount) than many of the better LPVO optics, such as the Vortex Viper/Razer. And finally, cuz I got a really good deal on the optic from another M4C member, with the scope already mounted in a LaRue CAT mount!
Lower Receiver
I’m a big fan of Forward Control’s Design components. They are generally well thought out and offer enhanced capability for shooting left handed. I wanted to build out a lower using as many FCD parts as possible. The Vltor A5 buffer system with Tactical Springs action spring was also chosen for its enhanced reliability.
I decided on a 2 stage trigger. The first several hundred rounds were shot using a LaRue MBT-2 trigger. Recently, I replaced the fire control with Centurion Arms new 2 stage trigger. I like the slightly rounded trigger shoe of the Geissele and Centurion triggers better than the 90 degree edge of the MBT-2 trigger. This is of course personal preference. The price point on LaRue and Centurion 2 stage triggers makes them a great option compared to the $200ish Geissele SSA trigger.
Estimated Round Count
800ish rds. 223 and 5.56 55gr FMJ of various manufacturers. Hornady Super Match 223 75gr OTM. CBC 5.56
77gr OTM/SMK. So far, rifle has been tested in the temperature ranges from 70 to 100 degrees. I have run slow fire for groups and used it in high volume of fire drills.
Observations
So far, I’ve gotten the best accuracy results from Hornady Supermatch 75gr OTM. CBC 77gr OTM also provided acceptable accuracy, though not as tight as the Hornady. Groupings at 100 yards are all under 2 MOA. When I am able to acquire Black Hills Mk 262/556 77gr OTM, I will see if it improves the accuracy over the Hornady.
POI shift with the SF suppressor is approximately 4 inches low and a ˝ inch to the left at 100 yards. The shift is consistent and the accuracy similar to unsuppressed.
The rifle has a peculiar knack for not locking back on the last round when using a gen 2 Pmag and resting the rifle on the mag. This does not occur with Okay or DH aluminum magazines or with Magpul Gen 3 magazines. Odd.
Build Specs
Upper
• Ballistic Advantage 16”, mid-length gas, Hanson profile barrel with pinned gas block and melonite gas tube
• Vltor MUR upper receiver
• LaRue Tactical 12” MLOK hand guard
• Sons of Liberty Gun Works BCG
• Radian Charging handle
• Surefire 556-212 flash hider & suppressor mount
Lower
• Sons of Liberty Gun Works lower receiver
• Forward Controls Design lower parts:
o EMR-A – enhanced mag release
o ABC/R v3 – Augmented Bolt Catch/Release
o ASF-90Q – Ambidextrous Selector, FC design, Q lever
o EMR-H – Enhanced Magazine Release, Heavy
o CNF – Castle Nut, FC Design
o PF040 – Pivot/Takedown pin, FC, .040
o TGF/W – Trigger guard, FC, Winter
o ESF-H1 QD End Plate
• Remainder of parts (springs and detents) supplied with SOLGW “blaster parts” kit
• LaRue Tactical MBT-2, 2 stage trigger or Centurion 2 stage trigger.
• Vltor A5 Receiver Extension, with A5H2 buffer and Tactical Springs “green” rifle action spring
• BCM pistol grip
• BCM Mod 0 Sopmod stock
Accessories
• Nightforce NX8 1x8 optic with LaRue Tactical CAT mount
• Magpul Pro front and rear BUIS
• Ferro Concepts Slingster 2 pt adj sling w/ QD attachment points
• Surefire 556-212 suppressor
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