How are the CMT HDM ARCA rails?

[redneckbmxer24]

I'm looking for a 15" Arca rail for a 6ARC and came across these, how are they? I'm looking for something similar in profile to the Geissele that's not from that asshat company. Are they somewhat slim like the Geissele or are they a horse cock like the sgt of arms rail? How is the barrel nut design and lockup? For those that have them, any complaints or reasons you'd go with a different rail? Does it clear an SLR AGB? Is there anything else I'm missing?

I'm looking to stick with something high quality and I know CMT stuff is. It will be going on a Vltor MUR1A receiver (or maybe a CMT or FCD) with a Proof CF 18" barrel.

 

[msgriff]

I'm interested in answers on the SLR fit, especially with barrel/rail flex. The ID of the CMT is pretty small.

 

[redneckbmxer24]

They claim it fits most adjustable gas blocks on the market but I haven't called to ask about the superlative clamp on. I know that the superlative clamp on will not fit in the Geissele ARCA rail. I bought one for a DMR upper I put together with one and it was close but not quite there. A set screw type may fit but I prefer the clamp on.

 

[TonyTheTiger]

It looks to be roughly based on the same extrusion as their regular HG's, which are pretty slim profile. Obviously the arca limits how slim it can be. If my guess is correct and they are the same I.D. as their standard stuff an SLR set screw AGB will fit fine. Not sure about a clamp on.
They are making these for IWI also, the only difference is that the IWI is shipped with a steel barrel nut vs. aluminum with the CMT.

 

[David Lepley]

I just posted some pics of my build with a Superlative Arms set screw with the CMT Arca, also on 6ARC.

 

[Annex Defense]

I've handled two that were undersized / would pass through the RRS NO-GO gauge for Dovetail spec; one of those was sent to us because they were having issues with it slipping in an Anvil head.

Please do not take this as a sales pitch for our ARCA to MLOK rails so much as it is feedback based on the very limited sample size we've had through our shop.

 

[Waco Kid]

I don’t have their arca handguard, but I have their mlok one that has sort of a short pic quadrail at the front end, forget what they call it. Not sure how similar they are near the top rail, but it sits over a Seekins agb and the fit is pretty tight. The Seekins is wider and tapered different on one side, and it’s really close on that side to the bottom corner of the gas tube cut out under the top rail. I’m almost sure it would touch under firing due to the clearance but I haven’t seen any evidence looking at. However the handguard and agb have only been on there maybe 100 rounds