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I have been installing a SureFire muzzle brake on a MR556A1. I thought I had it all figured out until I tried torqueing the device to 20 to 30 ft-lbs (SureFire's recommended value). I have discovered that using a Brownells Combination Wrench and a torque wrench, that I cannot successfully torque the device. The torque wrench will not "break" at the desired target torque. It just keeps tightening. I even got a second, new torque wrench to rule out a malfunctioning torque wrench. Perhaps I am doing something wrong or perhaps I have the wrong tool or perhaps I'm missing something. Any help or suggestions would be welcome. I have looked at some different tools as a potential solution. But I do not want to buy anything more until I know that my chance of success is good.

Other tools considered:

ARRINGTON ACCURACY WORKS - AR-15/M16 COLT LAW ENFORCEMENT CARBINE ARMORER'S WRENCH

Tapco Armorer's Tool

Thanks,
Rod Michael
 

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No idea what's going on with your torque wrench. I don't think you need the armorer's tools you mention, and it doesn't sound like you're doing anything wrong.

Best bet is to use a snap on torque wrench and an adapter. A cheapo harbor freight torque wrench will work too but if you splashed out on the MR556 then hopefully decent tools are in your budget.

This Snap-on Industrial Brand CDI Torque 2503MFRPH 1/2-Inch Drive Adjustable Micrometer Torque Wrench, Torque Range 30 to 250-Foot Pounds - Amazon.com

Plus this: Save on SK Hand Tool 42270 at ToolTopia.com

in a size that fits your comp.
 

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Are you using a crush washer, or shims?

If using a crush washer, just tighten it until the thing is straight. If using shims, shim it until you're at about 10 O'clock hand tight, then tighten it straight.
Most gunsmiths I know (paid) don't use torque wrenches for AR muzzle devices.

And a brownells or Geissele reaction rod makes life easy if you do this a lot.

-Dave
 

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I also had a lot of problems installing their 308 SOCOM muzzle brake. Their book showing the wheel of misery as I call it shows what shims you need to time the brake. Unfortunately the shims are not the thickness they were supposed to be and their procedure did not work for me. I had to put the spacer on then twist on the brake till it stopped against the spacer backed off till it was timed and measured the gap. Then put together the shims required to fill the space. Took 3 tries but finally got it. Put the Rocketset on just tightened it until it was timed.
 
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