Shim needed for muzzle device?

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Strider_z71 Joined May 2023 Posts 1 EE 0% (0) TX, USA	Posted: 4/28/2024 5:00:14 PM EDT I am putting a rearden R2S onto my 16" daniel to host a polonium k suppressor with atlas mount. The R2S threads fine all the way to the shoulder. Is a shim needed or am I good to torque directly to shoulder?

TGWLDR GUN WHORE Joined Dec 2014 Posts 49776 EE 100% (446) USA	Posted: 4/28/2024 5:31:07 PM EDT [#1] From their webpage: Shims not included, if you would like to specifically time this, shims will be required. Note: your barrel may require a shim if the manufacturer did not put a thread relief on it.
	Can't never could 'til try came along. "All welchers should be removed from the EE".-Aimless R.I.P. to the EE

Strider_z71 Joined May 2023 Posts 2 EE 0% (0) TX, USA	Posted: 4/28/2024 5:36:24 PM EDT [#2] Yes ive read that. It doesnt need timing, and it does not have a thread relief cut into it. I guess im asking what should I be looking for to determine if my barrel may need one?

EdgecrusherXES The door to immortality is shut Joined Jun 2007 Posts 36505 EE 0% (0) TX, USA	Posted: 4/30/2024 10:09:39 AM EDT [#3] Quote History Originally Posted By Strider_z71: Yes ive read that. It doesnt need timing, and it does not have a thread relief cut into it. I guess im asking what should I be looking for to determine if my barrel may need one? View Quote How much torque are you putting on it right now? 5, 10, 20, 30#?
	I know you can feel it let it in people will still hate you in the end. So hate back, plan the attack then they will realize they cannot crack the mind of a fucking maniac. The voice inside you always wins your grave's been dug so lie in it.

Strider_z71 Joined May 2023 Posts 3 EE 0% (0) TX, USA	Posted: 4/30/2024 5:31:35 PM EDT [#4] None yet, plan to torque to 25

DevL

Joined May 2002
Posts 23327
EE 100% (23)

TX, USA

Posted: 5/2/2024 6:43:14 AM EDT

[#5]

Quote History

Originally Posted By Strider_z71:e fuel
Yes ive read that. It doesnt need timing, and it does not have a thread relief cut into it. I guess im asking what should I be looking for to determine if my barrel may need one?

View Quote

Look at the barrel under the threads to see if tbey are relief cut or if the barrel just flares out at the base of the threads before the full barrel profile.

TGWLDR

GUN WHORE

Joined Dec 2014
Posts 49832
EE 100% (446)

USA

Posted: 5/2/2024 6:56:46 AM EDT

[#6]

Quote History

Originally Posted By Strider_z71:
Yes ive read that. It doesnt need timing, and it does not have a thread relief cut into it. I guess im asking what should I be looking for to determine if my barrel may need one?

View Quote

I've always used shims when no relief cut is present, timed devices or not.

So long as the mount indexes on the barrel shoulder and the shoulder is perpendicular to the bore it should be fine.

Can't never could 'til try came along.

"All welchers should be removed from the EE".-Aimless

R.I.P. to the EE