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8/21/2025 2:03:12 AM EDT
Is this a cap or spacer on the end of my RDB barrel, or is that ring with wrench flats part of the barrel? I'm thinking I should know this before I try to spin it off.

Attached File

Disclaimer - OP is bad at knowing things, and might catch on fire.
Vet - Op MMAMA
Every other species kills off their stupid......we cater to them. -- spin-drift
Nobody ever called 911&said I just did something smart. -- TheFlynDutchman
8/21/2025 2:33:10 AM EDT
[#1]
This might have been a dumb question - I've seen references to this being a jam nut for muzzle devices..... including item 141 in the parts list from the manual. "Compensator Nut"

It looks like I'm clear to take it off and see if I can spin on a reflex suppressor mount.
Disclaimer - OP is bad at knowing things, and might catch on fire.
Vet - Op MMAMA
Every other species kills off their stupid......we cater to them. -- spin-drift
Nobody ever called 911&said I just did something smart. -- TheFlynDutchman
8/21/2025 4:13:08 AM EDT
[#2]
Sometimes a nut like that is used because the barrel was to skinny for a proper shoulder. I know that can cause issues sometimes. Hopefully someone who know will chime in.
BikerNut:
Normal people like motorcycles. Real people like motorcycles.

People who don't like motorcycles are just... weird.
8/21/2025 10:01:25 AM EDT
[#3]
I still have mine on the rifle even after changing muzzle devices as the ones I use cant take up the additional threads that spacer takes up.
8/21/2025 10:15:18 AM EDT
[#4]
Its a compression nut for timing a muzzle device.
Redd Bingham
Guntech III
Brownells Inc.

https://lnk.bio/Redd_BrownellsGT
8/21/2025 6:02:21 PM EDT
[Last Edit: Amish_Bill][Edited] [#5]
Quote History
Originally Posted By ALASKANFIRE:
Sometimes a nut like that is used because the barrel was to skinny for a proper shoulder. I know that can cause issues sometimes. Hopefully someone who know will chime in.

Originally Posted By Odinforever2000:
I still have mine on the rifle even after changing muzzle devices as the ones I use cant take up the additional threads that spacer takes up.
View Quote
I am a bit concerned about how long the threading is. The flare approaching the threads is a hair over 0.70" so I think  I'll be in good shape if I need a precision spacer - assuming the existing nut does not tighted up square with a suppressor mount.
Disclaimer - OP is bad at knowing things, and might catch on fire.
Vet - Op MMAMA
Every other species kills off their stupid......we cater to them. -- spin-drift
Nobody ever called 911&said I just did something smart. -- TheFlynDutchman
8/21/2025 10:49:33 PM EDT
[#6]
Quote History
Originally Posted By Amish_Bill:
I am a bit concerned about how long the threading is. The flare approaching the threads is a hair over 0.70" so I think  I'll be in good shape if I need a precision spacer - assuming the existing nut does not tighted up square with a suppressor mount.
View Quote

I run a Hux mount with the spacer. Seems square to me.
8/21/2025 11:17:44 PM EDT
[Last Edit: Amish_Bill][Edited] [#7]
Quote History
Originally Posted By Odinforever2000:

I run a Hux mount with the spacer. Seems square to me.
View Quote
My biggest concern is diameter. I have an idea to use a reflex style muzzle device/mount, and it does not fit over that nut. In theory, I could spin it down to a workable diameter, but that involves taking it off, which also solves the problem, but with less work.
Disclaimer - OP is bad at knowing things, and might catch on fire.
Vet - Op MMAMA
Every other species kills off their stupid......we cater to them. -- spin-drift
Nobody ever called 911&said I just did something smart. -- TheFlynDutchman

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