[German]

Sorry, didn't see this thread sooner.

Does anyone know whether the QM (quick mount) fits the stock MR223 muzzle device?

Yes, I know.

And no, it doesn't.

In fact, I haven't found the DUAL556 with QM (only BL) in any shop, yet...

At least the distributor should have it. The German distributor does.
Most dealers don't know this model yet and so they don't order and stock it.

The alternative would be to go with the BL and muzzle break -- probably the Klärig Engineering one for M15x1, since this seems to fit the MR223 better than the Ase Utra muzzle device.

Go HK A2 flash hider with DUAL556 and don't look back.

Which makes:

Would you recommend this option?

A "Yes!".

Bascially, the QM mounts are compatible with NATO flash hiders that have such a locking groove (1):

That picture actually shows the HK-234182 made for HK 416 / HK MR223 / HK417 / HK MR308 / G28 / HK243.

The civilian versions (MR223) of the HK416 don't have that, so in any case, it's necessary to change the muzzle device for the MR223s.

Correct.

HK should have the flash hider above in stock, so your local distributor (Austria?) should be able to order it if he has them not in stock, so your local dealer can get it from them for you... Yeah, HKs idea of their European distribution channels suck.

Here available in Germany for example.

 

[German]

Just snapped a few quick pictures for you:

HK-234182 flash suppressor

HK-234182 flash suppressor mounted on MR223A3

Ase Utra DUAL556-S-QM2 mounted on HK-234182

 

[German]

the HK-234182 flash suppressor is an untimed device, correct? Just bolt onto the barrel without shims?

Unfortunately, yes. Contrary to an "real" A2 Flash hider there is no closed part preventing dust/debris being kicked off the ground.

So it does not need timing.

If the OCD is strong enough, one could use shims to get the flats the QM2 locks onto aligned either vertically or horizontally (with a vertical alignment being favorable so you can position the ratchet-release lever at 12'o clock for better accessibility).

I'll probably do that at some point in time. For now it works as it is.

Is the mounting mechanism of the Ase Utra DUAL556-S-QM2 as secure/accurate as with a dedicated Borelock muzzle device?

I think the design is more clever and less cumbersome than the Borelock system but it has a few more moving parts. And it mounts to rather affordable "standard" flash hiders (although HK decided to put non-standard stuff on their MRs, who would have thought...) so you don't have to buy a more pricey Borelock-compatible device.

Moveable (and thus breakable) parts are in favor of Borelock.
Here the B&T (M.A.R.S.) QDM mount leads the pack IMHO.
Their (Rotex V/X) QDN A2 mount on the other hand also has quite a few parts.

 

[German]

As a visualisation:

B&T QDM (3 moving parts)

B&T QDN (8 moving parts)

Ase Utra BL (5 moving parts)

Ase Utra QM2 (manual doesn't show an exploded view, my count is about 15 moving parts)

 

[German]

The barrel you showed previously is 14.5"

Yes.

But the suppressor gets switched between different guns from 10.5" to 16.5" for T&E.

What are your thoughts on the short Ase Utra vs. full size?

I'm not interested in maximum achievable suppression but just want to reduce the blast level and flash and rather have a shorter overall length (and a tiny bit less weight at the muzzle, the DUAL556-QM2 line is already heavy as it is, with an additional 135 grams over the BL model).

So my opinion might not be unbiased.

Those 2 dB difference in suppression that Ase Utra postulates won't be noticeable to the human ear (with the suppressor/caliber combination not being hearing safe anyway) and a flow through design will always be louder.

thinking with the larger one it might get a bit unwieldy.

Thats what I want do avoid.