just better then a USA Colt AR.
6933 will have a better resale value over CC MRR. Just look at what they're going for in the EE. They're far more rare up here than the MRR will be once released.
CC makes a good product but I personally want nothing to do with the MRR. It unnecessarily adds weight, uses proprietary parts and doesn't have a FSB.
Not a big fan of monolithic uppers that require the use of a huge tubular barrel wrench , purely from the perspective as a guy who maintains his own weapons.
Since I don't have a full shop supported by the factory with their tools and jigs, it is a PITA to service a system like the MRR and IUR. It is essentially the same barrel nut system used by KAC URX 8 to 10 years go. The gas block needs to come off to insert the barrel wrench. The assemble could be efficient at the factory when a line is set up, but a major PITA for a small shop or a guy in the basement unless you make your own tools or have the factory tools, and the PITA-ness will depend how exactly the gas block is affixed to the barrel. If it is not pinned, you may need another special tool. I can even service hk416 at home, so this throw back to the old barrel nut system doesn't excite me much. The later KAC URX and colt USA monolithic upper can be wrenched from the bottom, even the early Dutch IUR.
The best system is hk 416 which Giessele lifted off ( and then copied by all others in different variations). Easy to wrench and no need to index. While monolithic upper with close bottom looks cool aesthetically, it is not armorer friendly unless you are supported by factory proprietary tools and jigs.
Not a big fan of monolithic uppers that require the use of a huge tubular barrel wrench , purely from the perspective as a guy who maintains his own weapons.
Since I don't have a full shop supported by the factory with their tools and jigs, it is a PITA to service a system like the MRR and IUR. It is essentially the same barrel nut system used by KAC URX 8 to 10 years go. The gas block needs to come off to insert the barrel wrench. The assemble could be efficient at the factory when a line is set up, but a major PITA for a small shop or a guy in the basement unless you make your own tools or have the factory tools ( which will be a 12" bored out hardened steel bar), and the PITA-ness will depend how exactly the gas block is affixed to the barrel. If it is not pinned, you may need another special tool to unscrew it from the barrel. I can even service hk416 at home, so this throw back to the old barrel nut system doesn't excite me much. The later KAC URX and colt USA monolithic upper can be wrenched from the bottom, even the early Dutch IUR.
The best system is hk 416 grooved barrel nut which Giessele lifted off ( and then copied by all others in different variations). Easy to wrench and no need to index. While monolithic upper with close bottom looks cool aesthetically, it is not armorer friendly unless you are supported by factory proprietary tools and jigs.
If CC sold these barrel nut wrenches for their IURs, that would be a huge bonus...too bad it will probably never happen.
The barrel wrench will be at least a 12" bored out steel bar. The KAC one for the old URX costs 300 USD
This is what it looks like to do this kind of barrel nut system:
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Also, depending on the depth of the slots on the barrel nut, if you are not careful with the installation and let the wrench slips over the slots, you can damage the nut and can never get it out. Remember, you are trying to apply torque at least 10-12" from the nut, it is like working with a long socket with small engaging tooth. So preferably, you want a fixture that will hold on to the receiver instead of an extension rod that is popular these days.
See why I don't like this at all, unless properly made tools and fixtures are around. Not a surprise the guys at Calgary want to charge 140 dollars to swap barrels!



























