Are Crush Washers Necessary for Flash Hiders?

you can buy them separately and it's a good idea to use one if you can

If you want it clocked a specific way and don’t have a set screw, jam nut, thread locker or other means to lock it at that position (or a way to machine it so it bottoms against the shoulder at that position), a crush washer is helpful.

So no, they are not necessary for the job but are an easy method to implement.

As @jmorris said the crush washer is only really needed if your trying to clock the rotational position of the muzzle device.

The one thing to potentially be aware of, don't use a crush washer with a suppressor mount as they can allow enough misalignment to put an end cap in danger. If you need to clock a suppressor mount use shim washers.

The A1 flash suppressor had 6 ports and used a simple split-ring lock washer.

On the A2 one of the ports on the flash suppressor was eliminated and the name was changed to "compensator". The split-ring lock washer was replaced with the crush washer to clock the compensator so there was no port on the bottom.

Shawn Dodson said:

The A1 flash suppressor had 6 ports and used a simple split-ring lock washer.

On the A2 one of the ports on the flash suppressor was eliminated and the name was changed to "compensator". The split-ring lock washer was replaced with the crush washer to clock the compensator so there was no port on the bottom.

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So theoretically if your A2 hider clocked perfectly with an ordinary lock washer you would be GTG?

mshootnit said:

So theoretically if your A2 hider clocked perfectly with an ordinary lock washer you would be GTG?

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Yup!

mshootnit said:

So theoretically if your A2 hider clocked perfectly with an ordinary lock washer you would be GTG?

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I don't even use a lock washer on my breaks or flash hiders If they match the barrel contour I just sand the base till they time properly.
Havent had one pop off yet.

If the brake or flash hider is larger ill usually stick a crush washer on there just to get a transition rather than an abrupt shoulder.

Opps should have said timed properly when torqued.

Shawn Dodson said:

On the A2 one of the ports on the flash suppressor was eliminated and the name was changed to "compensator". The split-ring lock washer was replaced with the crush washer to clock the compensator so there was no port on the bottom.

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Actually the peel washer came before the crush washer. (The peel washer is made of thin layers sandwiched together. You heat it with a match to remove as many layers as you need to index the muzzle device properly.)

I always preferred the peel washer to the crush washer. It seemed to me that the crush washer was a lazy solution.

In doing my latest builds, I found that peel washers are now difficult to obtain. Instead, there are kits containing a variety of thin washers, that you stack together to get the desired thickness. This is the same general idea as the peel washer, but it's an additive process rather than a subtractive process.

For the price, crush washers work fine. I never liked the split washer on the A1, they tended to open in diameter when torqued down, makes for a sloppy look.

Like already said if the hider fits correctly they aren't necessary and there are methods to make the hider fit correctly that are easy to do and remove the need for a washer. Personally I find no need for a hider on any of my firearms.Thread protector only is what I use.

LoonWulf said:

I don't even use a lock washer on my breaks or flash hiders If they match the barrel contour I just sand the base till they time properly.
Havent had one pop off yet.

If the brake or flash hider is larger ill usually stick a crush washer on there just to get a transition rather than an abrupt shoulder.

Click to expand...

I wouldn't try that if a suppressor is involved, unless sanding involved a lathe

mavracer said:

I wouldn't try that if a suppressor is involved, unless sanding involved a lathe

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I wouldn't even do it with a long tight brake.
But all of mine are short and a suppressor isnt an option.

You can also do away with the crush washer by using a Precision Armament Accu-Washer to clock your muzzle device.