Crush Washer Question

[mmattockx]

I have a stupid question regarding the crush washer for the A2 flash hider - which way does it go on, cone towards the barrel or the hider? Or does it matter at all?


Thanks,
Mark

 

[C77]

The wide end goes forward on a standard bbl. A sleeved barrel, like C8A3 the narrow end forward.

Min 90 degrees from hand tight, no more than one full turn past that.

 

[Runningfool]

It matters. Cup facing FH.

edited to add C77 beat me to it!

 

[mmattockx]

Awesome, thanks.


Mark

 

[C77]

I'm from the Government. I'm here to help.

 

[Onagoth]

Aren't you supposed to replace the crush washers once the FH or other muzzle device has been removed?

EDIT: Actually, its not clear whether or not the OP is re-using one, so this post was mostly an assumption

 

[C77]

Aren't you supposed to replace the crush washers once the FH or other muzzle device has been removed?

Yes. They are one time use. If you re-use them there is a good chance of flying FH. That's why CF does not use on C7A2 - partly.

 

[Jäger1]

You can resurrect a used crush washer by applying heat to it sometimes.

 

[C77]

You can resurrect a used crush washer by applying heat to it sometimes.

Seems like a bad idea. How will heat un crush a mechanical torque limiting washer? Why do you think that?

 

[mmattockx]

Aren't you supposed to replace the crush washers once the FH or other muzzle device has been removed?

EDIT: Actually, its not clear whether or not the OP is re-using one, so this post was mostly an assumption

I didn't say, but it is a new flash hider going on a new barrel and I didn't have an old one to compare with for the orientation.


Mark

 

[Jäger1]

Seems like a bad idea. How will heat un crush a mechanical torque limiting washer? Why do you think that?

It's my understanding that heating the metal to a bright glow and letting it cool slowly softens it up and may give you more "crush", potentially allowing you to get a second use out of it.

 

[Onagoth]

It's my understanding that heating the metal to a bright glow and letting it cool slowly softens it up and may give you more "crush", potentially allowing you to get a second use out of it.

Doesn't a crush washer cost like, I dunno, 2 bucks?

 

[Onagoth]

It's my understanding that heating the metal to a bright glow and letting it cool slowly softens it up and may give you more "crush", potentially allowing you to get a second use out of it.

Doesn't a crush washer cost like, I dunno, 2 bucks?

 

[Jäger1]

Doesn't a crush washer cost like, I dunno, 2 bucks?

Yeah, maybe less. I've never tried it myself but I had heard it from multiple sources. Thought I'd share the info. I can see the appeal when a lot of stocking dealers have crush washers for $2.99 and charge $13 flat rate shipping.

 

[C77]

Doesn't a crush washer cost like, I dunno, 2 bucks?

This.

Also, auto mechanics used to say that about copper crush washers for oil drains. Not the same.

If you reuse these, chances are they will pancake out and engage the threads forcing you to cut it off next time it needs to be removed.

Heat treating is a little more complicated than making it glow. You will either make it too brittle or too soft. The torque limiting feature comes from the shape and how it collapses.

A flash hider coming off might get loose, fall off, or get shot and shower people with fragments. Not worth it to save a buck or two I'd say.

 

[badboybeeson]

While we are at it. Does anyone know what the washers are made of??

 

[mmattockx]

While we are at it. Does anyone know what the washers are made of??

The one I asked about in OP holds a magnet, so it is some type of steel. Likely a low carbon steel to get enough ductility for the deformation it sees.


Mark