reinstalling of flash hider

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[ARCHIVED THREAD] - reinstalling of flash hider

Posted: 11/28/2014 10:12:41 PM EDT

Hello all. I have only removed a FH once before to change out a gas block. When I put it back on, I cleaned the threads with break cleaner and put a small dab of slip2000ewl on threads and tightened it up. I am about to put another one on and read that some people put a grease on the threads. Is it necessary? If so can I use lubriplate 130a?

One other thing, I only have one new crush washer left plus the used one I had from removing my FH. The new crush washer and FH hand tightens to 12 o'clock. It is aligned perfectly with out tightening it down. Will it be a problem to wrench down another 360 degrees to align the FH? Should I lightly remove some material from it so it times by hand better. The used crush washer times at about 9 o'clock by hand which is about right. However I was told to never reuse a crush washer. What should I do?

Posted: 11/28/2014 11:42:01 PM EDT

[#1]

You should be able to put a full turn on the new crush washer no problem.

The old one probably won't offer enough resistance when you crank it to 12 o'clock.

Although the cheapskate in me says just re-use it and ad a dab of locktite. (Not recommended.)

Posted: 11/29/2014 10:12:45 AM EDT

[#2]

Personally, I'm not a fan of ultra tight muzzle devices, strictly flash hiders in my case. They are more difficult to remove to keep the barrel crown clean, and (in the case of 1/2-28 threads) they reportedly put too much compression on the bore thereby interfering with accuracy.

My preference is to tighten with a wrench, more than finger tight, but not much more. If I want to time the angular position of the FH, I remove small amounts of metal with sandpaper from the underside of the crush washer, rather than compress it substantially. One added benefit, I can use the same washer indefinitely. - CW

Posted: 11/29/2014 10:32:05 AM EDT

[#3]

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Quoted:
Personally, I'm not a fan of ultra tight muzzle devices, strictly flash hiders in my case. They are more difficult to remove to keep the barrel crown clean, and (in the case of 1/2-28 threads) they reportedly put too much compression on the bore thereby interfering with accuracy.

My preference is to tighten with a wrench, more than finger tight, but not much more. If I want to time the angular position of the FH, I remove small amounts of metal with sandpaper from the underside of the crush washer, rather than compress it substantially. One added benefit, I can use the same washer indefinitely. - CW

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I would think you'd strip the threads off of the hider and/or barrel before you applied enough force to deform the barrel to the point of accuracy problems.

Posted: 11/29/2014 10:51:31 AM EDT

[#4]

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Quoted:

I would think you'd strip the threads off of the hider and/or barrel before you applied enough force to deform the barrel to the point of accuracy problems.

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Quoted:

Quoted:
Personally, I'm not a fan of ultra tight muzzle devices, strictly flash hiders in my case. They are more difficult to remove to keep the barrel crown clean, and (in the case of 1/2-28 threads) they reportedly put too much compression on the bore thereby interfering with accuracy.

My preference is to tighten with a wrench, more than finger tight, but not much more. If I want to time the angular position of the FH, I remove small amounts of metal with sandpaper from the underside of the crush washer, rather than compress it substantially. One added benefit, I can use the same washer indefinitely. - CW

I would think you'd strip the threads off of the hider and/or barrel before you applied enough force to deform the barrel to the point of accuracy problems.

I got this caution from Harrison at AR Performance, a premier AR barrel maker. All of his barrels, with the exception of an ultralight 5.56 model, have 5/8-24 threads to eliminate any possible swelling (not compression) 0f the bore at that point. Apparently, the distortion occurs when the threads are cut rather than when the MD is torqued down (my mistake above). I figure he ought to know. - CW

Posted: 11/29/2014 11:16:32 AM EDT

[#5]

I reused the old one. It still had some crush left. I didn't have a barrel vice so I clamped wood around my barrel and fsb. I tightened it up very tight and the fsb helped keep the barrel from turning while indexed the FH. The fsb leveraged against some of the wood and helped keep the barrel from rotating. All good to go.

Posted: 11/29/2014 11:36:19 AM EDT

[#6]

Never reuse a crush washer, they are a one time use item just like roll pins.

Also, using moly grease on the threads is a good idea.

I would also recommend against using the standard mil-spec crush washers because they can cause you to apply way to much torque.

I recommend using the Armageddon Tactical crush washers as they are designed to crush between the 15-20 foot pound torque spec.

Posted: 11/29/2014 12:24:06 PM EDT

[#7]

Quote History

Quoted:
Never reuse a crush washer, they are a one time use item just like roll pins.

Also, using moly grease on the threads is a good idea.

I would also recommend against using the standard mil-spec crush washers because they can cause you to apply way to much torque.

I recommend using the Armageddon Tactical crush washers as they are designed to crush between the 15-20 foot pound torque spec.

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OK. So stupid question is the lubriplate 130aa OK to use or should I get a different grease? I can easily enough remove the FH and use the recommended crush washer.

Posted: 11/29/2014 12:42:14 PM EDT

[#8]

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Quoted:

OK. So stupid question is the lubriplate 130aa OK to use or should I get a different grease? I can easily enough remove the FH and use the recommended crush washer.

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Quoted:

Quoted:
Never reuse a crush washer, they are a one time use item just like roll pins.

Also, using moly grease on the threads is a good idea.

I would also recommend against using the standard mil-spec crush washers because they can cause you to apply way to much torque.

I recommend using the Armageddon Tactical crush washers as they are designed to crush between the 15-20 foot pound torque spec.

OK. So stupid question is the lubriplate 130aa OK to use or should I get a different grease? I can easily enough remove the FH and use the recommended crush washer.

It will probably work okay.

I just use moly grease because I have it and use it on barrel nuts and castle nuts as well.

Posted: 11/29/2014 1:17:05 PM EDT

[#9]

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Quoted:

It will probably work okay.

I just use moly grease because I have it and use it on barrel nuts and castle nuts as well.

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Quoted:

Quoted:
Never reuse a crush washer, they are a one time use item just like roll pins.

Also, using moly grease on the threads is a good idea.

I would also recommend against using the standard mil-spec crush washers because they can cause you to apply way to much torque.

I recommend using the Armageddon Tactical crush washers as they are designed to crush between the 15-20 foot pound torque spec.

OK. So stupid question is the lubriplate 130aa OK to use or should I get a different grease? I can easily enough remove the FH and use the recommended crush washer.

It will probably work okay.

I just use moly grease because I have it and use it on barrel nuts and castle nuts as well.

OK. I just dabbed some lubriplate on my fingers and smeared it around the threads. I didnt put a lot but a little bit. I wasn't sure how much to use. I assume this is to help it release when you remove the hider again in the future?

Also, one last thing. I know it is recommended to use a new washer but what if it is the same barrel/washer/ FH combo? I am debating on leaving it since it is already in place. Like i said, the old washer timed by hand to 9 oclock and then I worked it to 12 oclock and it appears pretty darn snug.

Posted: 11/29/2014 3:15:35 PM EDT

[#10]

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Quoted:

OK. I just dabbed some lubriplate on my fingers and smeared it around the threads. I didnt put a lot but a little bit. I wasn't sure how much to use. I assume this is to help it release when you remove the hider again in the future?

The grease should help prevent galling of the threads and depending on how good the particular grease used stands up to high temperatures it may make it easier to remove in the future.

Also, one last thing. I know it is recommended to use a new washer but what if it is the same barrel/washer/ FH combo? I am debating on leaving it since it is already in place. Like i said, the old washer timed by hand to 9 oclock and then I worked it to 12 oclock and it appears pretty darn snug.

It doesn't matter if it is the same barrel/washer/muzzle device combination you are always supposed to use a new one. You might get away with it without having any problems but reusing one time use only parts is not for me.

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Quoted:

Quoted:
Never reuse a crush washer, they are a one time use item just like roll pins.

Also, using moly grease on the threads is a good idea.

I would also recommend against using the standard mil-spec crush washers because they can cause you to apply way to much torque.

I recommend using the Armageddon Tactical crush washers as they are designed to crush between the 15-20 foot pound torque spec.

OK. So stupid question is the lubriplate 130aa OK to use or should I get a different grease? I can easily enough remove the FH and use the recommended crush washer.

It will probably work okay.

I just use moly grease because I have it and use it on barrel nuts and castle nuts as well.

OK. I just dabbed some lubriplate on my fingers and smeared it around the threads. I didnt put a lot but a little bit. I wasn't sure how much to use. I assume this is to help it release when you remove the hider again in the future?

The grease should help prevent galling of the threads and depending on how good the particular grease used stands up to high temperatures it may make it easier to remove in the future.

Also, one last thing. I know it is recommended to use a new washer but what if it is the same barrel/washer/ FH combo? I am debating on leaving it since it is already in place. Like i said, the old washer timed by hand to 9 oclock and then I worked it to 12 oclock and it appears pretty darn snug.

It doesn't matter if it is the same barrel/washer/muzzle device combination you are always supposed to use a new one. You might get away with it without having any problems but reusing one time use only parts is not for me.

Posted: 11/29/2014 5:17:18 PM EDT

[#11]

Crush washers by design should be able to go 1-1/4 turns from contact.
They should be installed with a minimum of ¼ turn.
I use barrel assembly grease.
If I were out (not likely) I would use the anti-seize I use for my shotgun chokes.
I don’t see this as a Lubriplate application, but YMMV.

Posted: 11/29/2014 6:30:49 PM EDT

[#12]

If I run to an auto shop, what moly grease would you recommend? I am probably going to dusassembe and redo it.

Posted: 11/29/2014 7:08:18 PM EDT

[#13]

I use Brownells Barrel Assembly Paste and have used NECO Moly-Slide.

The mil-spec grease is Areoshell 33MS.

I don't know if an auto shop will have it but if they do get this. > http://www.henkelna.com/industrial/product-search-1554.htm?nodeid=8797877698561

Posted: 11/29/2014 7:31:58 PM EDT

[#14]

http://m.autozone.com/autozone-mobile/en/accessories/AGS-Wheel-bearing-grease-pouch/_/N-25ap?id=352008

Would this work? I have this.

Posted: 11/29/2014 7:37:49 PM EDT

[#15]

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Quoted:
http://m.autozone.com/autozone-mobile/en/accessories/AGS-Wheel-bearing-grease-pouch/_/N-25ap?id=352008

Would this work? I have this.

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It would probably work but there is no moly in it.

Really almost any grease or anti seize would work for muzzle device installation. Most manufacturers don't even use anything on the muzzle threads.