How important is indexing your flash suppressor...?

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SilentStalker

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So, I pulled out one of my ARs the other day and noticed that the flash suppressor is not indexed properly. It's like it is tightened down too far. The gun was bought used years ago and I don't really see it as a big deal but it bothers me. While I am mechanically inclined I don't have anythin to hold this with to index it correctly. So, should I try to makeshift something to hold the rifle and index it correctly or should I just take it to a smith when I take one of my other rifles for scope mounting that I cannot seem to get right.
 
One of the things about an improperly indexed flash suppresor is that if you ever shoot it prone in the dirt you'll get more dirt from the blast in the air, if you look at your birdcage you'll notice that a portion is solid (no slots) that keeps the blast directed to the sides and uppwards instead of into the dirt/ground.
 
You can try and peel a couple of layers off the crush washer and see if you can get it timed up. At worst, you just need to get a new washer and do the same thing.
 
SilentStalker said:
How important is indexing your flash suppressor...?
So, I pulled out one of my ARs the other day and noticed that the flash suppressor is not indexed properly. It's like it is tightened down too far. The gun was bought used years ago and I don't really see it as a big deal but it bothers me. While I am mechanically inclined I don't have anythin to hold this with to index it correctly. So, should I try to makeshift something to hold the rifle and index it correctly or should I just take it to a smith when I take one of my other rifles for scope mounting that I cannot seem to get right.

If a crooked flash suppressor is bothering you, then have at least someone with the right tools do the work. If you "make shift" something and end up putting an "idiot mark" on your gear, that "bother" you have from the crooked flash suppressor will be permanent. It's an easy fix, but if you don't have the correct tools, you'll make a blemish that "bothers you" more!
 
If it's been that way for years & you're just now noticing, I'd say it has no importance whatever unless it's upside down.
Denis
 
The peel washer and the crush washer are two different things. Both are means of indexing the asymmetrical birdcage flashhider so that the solid portion is on the bottom. (The peel washer was the earlier design.) With the peel washer, you remove layers (easy if you use the heat of a match) until the FH lines up. With the crush washer, you hand tighten and then use torque (sometimes quite a bit of torque) until it lines up. I personally much prefer the peel washer.

If you have an over-torqued crush washer (that sounds like what you have), you may have a real problem removing the FH. You could try clamping the barrel in a barrel vise fixture and then using a big wrench on the FH. Or, you could do what I did and use a cutoff wheel in a Dremel tool to very carefully grind a relief groove all around the crush washer. (Don't go too deep and cut into the barrel threads!) This relieves the tension so that you can easily remove the FH with a wrench.

You're going to need a new peel or crush washer to reinstall.
 
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I replaced the birdcage on my AR with a wrench and a crush washer. No idiot marks, nothing broke. Just take the upper off, take off any accessories and get the muzzle device tight, then turn to index. Its a bit tough, but it works great and I got it clocked in at the range. It does help to have an A2 upper though.

YMMV
 
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