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deadon57
04-29-12, 21:13
I found with the muzzle brake that I have, just using a crush washer doesn't allow me to have it indexed properly so I bought some peel washers. For clarity sakes, I do use the peel washers in conjunction with the crush washer to get a proper indexing, correct?
Robb Jensen
04-29-12, 21:18
You use one type or other.
deadon57
04-29-12, 21:32
Thank you, this helps
snakedoctor
04-29-12, 21:37
What brake are you installing?
deadon57
04-30-12, 21:32
What brake are you installing?

I got rid of the plastic bag it was in and I got it long time ago. It came with a crush washer, but its very apparent that I need to use peel washers because its just not indexing correctly.
PRGGodfather
04-30-12, 21:54
Be sure to use a fresh, new crush washer.

Use plenty of lube; anti-seize preferred.

Orient the crush washer with the flared side towards the muzzle device, and the narrow end against the barrel shoulder.

"Crush" the washer using a minimum of 20, and a maximum of 45 lbs. of torque.

If you have a long way to go, only do quarter turns and then back it off. You will crush it incrementally about 1/8th of a turn at a time. Sneak up on the timing, because once it is properly oriented, you do NOT want to back it off.

Good luck.
KyAKGuy
04-30-12, 22:42
If you really want to take the time, you can actually use a wetstone to take the crush washer down to a point where you can get it where it needs to be to do the final tightening on it. It doesn't take too long to do and just takes a little trial and error as to mow much you need to take off and how it indexes. Hit the new surface with a little cold blue and you will never see it. I've done several this way and have always had good results, and never have had a problem with them staying tight.

KyAKGuy
Hmac
05-01-12, 00:17
I got rid of the plastic bag it was in and I got it long time ago. It came with a crush washer, but its very apparent that I need to use peel washers because its just not indexing correctly.

I suspect you don't know how to use a crush washer. Since they will crush over more than 360 degrees, it's virtually impossible for them not to allow proper indexing.
Iraqgunz
05-01-12, 01:45
I think you are right.


I suspect you don't know how to use a crush washer. Since they will crush over more than 360 degrees, it's virtually impossible for them not to allow proper indexing.
Brahmzy
05-01-12, 12:34
If you really want to take the time, you can actually use a wetstone to take the crush washer down to a point where you can get it where it needs to be to do the final tightening on it. It doesn't take too long to do and just takes a little trial and error as to mow much you need to take off and how it indexes. Hit the new surface with a little cold blue and you will never see it. I've done several this way and have always had good results, and never have had a problem with them staying tight.

KyAKGuy

This is what I do as well. I cannot count the # of AR rifles I've built/rebarreled etc., but I have always struggled with crush washers. The sheer amount of torque that's required seems like an obscene amount of stress on the muzzle area metal. I've put crush washers in my vise before and been absolutely unable to crush them - IN A VISE. So I started buying my crush washers from somewhere else - same thing. Was told to buy YHM crush washers - same thing. I despise peel washers, so I usually just end up carefully filing crush washers down to fit perfectly (tight, but not torque'd to hell on the threads.)
Bill Alexander
05-05-12, 08:42
The crush washer is essentially a conical washer manufactured of 302 stainless steel. Like most pieces of steel, the bar from which these are made, may be in a variety of states, not least it may be cold rolled in its final form and as this steel type is a work hardening grade, it may too hard to fulfill its function even as manufactured. YHM crush washers are typically in the dead soft or normalized state as supplied and are among the best of these parts.

The washer orientation on the barrel results from the need to provide an even pressure on the back of the flash hider and hence hold it square, as far as is possible, on the muzzle threads. Originally the washer was fitted to deform against the shoulder of the barrel but this left the flash hider resting against the small diameter and more likely to be forced off axis, hence the orientation is important. One of my pet peaves is the use of 5/8-24 threads on barrels set for 0.750 gas blocks. The gas block diameter precludes the use of sufficient shoulder on the barrel behind the thread to correctly locate the washer edge. Blackout barrels requiring this thread pattern are problematic so a non indexing muzzle attachment is the best selection.

It is extremely difficult to deform a crush washer in a vice. For problematic combinations a barrel stub is the best solution. Noting the rotation required, the crush washer may be set on this "dummy" assembly and then transfered to the intended build for slight final tightening.

The original peel washers were laminated from stainless and phenolic. It was found is some instances that the phenolic would degrade between the shims and the flash hider would be left without tension and free to rotate.
14point5
05-08-12, 16:42
If you have a long way to go, only do quarter turns and then back it off. You will crush it incrementally about 1/8th of a turn at a time. Sneak up on the timing, because once it is properly oriented, you do NOT want to back it off.



I believe many people do not know how to work a crush washer into the desired position.
PRGGodfather
05-08-12, 21:15
I believe many people do not know how to work a crush washer into the desired position.

You're probably right. That's why our legal team suggested we put "Professional Installation Required" on the label, rather than lengthy instructions. We were sadly surprised when we found a good number of "gunsmiths," who didn't seem to know how to orient them, either.
wingo
05-09-12, 20:24
Some good taps with a hammer on a flat surface can start the crush or get closer to the indexing point.
dhena81
05-11-12, 14:49
I'd go to home depot and grab a can of elbow grease :smile: and torque that sucker down preferably in a barrel vise.

I've always started torquing and then backing off repeatably until I would get the correct orientation. At the same time they are a one use item. So does the above method affect the attachment or compromise the crush washer?
Hmac
05-11-12, 18:01
I'd go to home depot and grab a can of elbow grease :smile: and torque that sucker down preferably in a barrel vise.
...

I've always started torquing and then backing off repeatably until I would get the correct orientation.

Yep, in my experience it's just that simple.