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Chambering Recomendations for SBR

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Category: Firearms, Bows, and Ammunition
Forum Name: Firearms
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Printed Date: March/19/2024 at 06:56
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Topic: Chambering Recomendations for SBR
Posted By: SVT_Tactical
Subject: Chambering Recomendations for SBR
Date Posted: March/27/2018 at 10:23

I'm overthinking allot her lately and want some advise or reassurance.   For a SBR AR what chambering would you recommend that would equate to the flattest shooting round out to say 250yds all while trying to keep a barrel length less than 14.5?   Maybe I'm chasing something that can't be done and need that told to me.

What I'm wanting is to be able to zero around 200 ish and still be within 1-3" at distance from 25yds - 250yds so I could still aim at the center mass of a running coyote or hog and without worrying about holdover make a quick shot.

My current thinking is a 10"-12" Grendel shooting the 90gr bullets around 2400ish FPS..... Thoughts?



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"Most folks are about as happy as they make their minds up to be" - Abraham Lincoln



Replies:
Posted By: supertool73
Date Posted: March/27/2018 at 11:39
Look at a 6.8 spc.  They velocity drom from a 16" barrel to a 12" is not to bad.   With a 12" barrel and shoot 85 grain tsx bullets,  Data I am seeing is in the 26 to 2700ish fps

Also a 11.5 to 12" .223 and shoot 65 grain sierra game kings.  They do well on yotes. 


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Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: Tip69
Date Posted: March/27/2018 at 14:37
I didn't look at a short barrel... cause prolly not enough for hogs... but we love the .204 on yotes out to 300 yds

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take em!


Posted By: koshkin
Date Posted: March/27/2018 at 18:05
You are overthinking it.

Within 250 yards, 5.56x45, 6x45, 6.8SPC and 6.5Grendel will be virtually indistinguishable from each other in terms of trajectory as long as you stay with bullets in the 75-110 grain range.  Even supersonic Blackout has MPBR for a 6" target of about 230yards with 110gr Barnes out of a 14" barrel.

Pick whichever cartridge you are already set-up for.

ILya


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http://www.darklordofoptics.com - www.darklordofoptics.com
https://rumble.com/c/DLO - Rumble Video Channel


Posted By: Rancid Coolaid
Date Posted: March/27/2018 at 20:09
At 200 yards, any 3 MOA rig will do.

I run SBRs and most are 556 running heavier bullets for caliber with fast twist. You can go exotic, but why? Do whatever you have ammo for, it’s 200 yards. You could throw a nail at 200 yards and kill a yote.

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Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.


Posted By: helo18
Date Posted: March/27/2018 at 21:02
I would curious as to which would be quieter.  I run a 10.5" 5.56 with a suppressor and it is still loud enough I like ear plugs.  I may build a short barrel 6.5 grendel just to see what happens.

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To be prepared for War is one of the most effectual means of preserving peace.

GEORGE WASHINGTON


Posted By: koshkin
Date Posted: March/27/2018 at 23:32
I do not think you will see any perceptible difference in sound with these calibers that are of similar velocity.

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http://www.darklordofoptics.com - www.darklordofoptics.com
https://rumble.com/c/DLO - Rumble Video Channel


Posted By: SVT_Tactical
Date Posted: March/28/2018 at 09:25
Originally posted by koshkin koshkin wrote:

You are overthinking it.

Within 250 yards, 5.56x45, 6x45, 6.8SPC and 6.5Grendel will be virtually indistinguishable from each other in terms of trajectory as long as you stay with bullets in the 75-110 grain range.  Even supersonic Blackout has MPBR for a 6" target of about 230yards with 110gr Barnes out of a 14" barrel.

Pick whichever cartridge you are already set-up for.

ILya


Thanks..... I'm going to look at using my blackout I already have with supersonic ammo and do some testing.... its an 8" barrel now but thinking slightly more would be better here but if I can make 8" work I will.



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"Most folks are about as happy as they make their minds up to be" - Abraham Lincoln


Posted By: Rancid Coolaid
Date Posted: March/28/2018 at 10:06
Originally posted by helo18 helo18 wrote:

I would curious as to which would be quieter.  I run a 10.5" 5.56 with a suppressor and it is still loud enough I like ear plugs.  I may build a short barrel 6.5 grendel just to see what happens.

What can are you using?
Are you shooting indoors or heavy woods/other structures?

At its core, short barrel is loud barrel.

I run a 10.5" SBR quite often and it is comfortable outside and in open spaces, but yea, gets uncomfortable in environments where sound can bounce around.  If you are using a 30-cal can on a 223, I have found them to be louder, even though they have higher volume.  This is anecdotal, no metered data to substantiate it. 


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Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.


Posted By: supertool73
Date Posted: March/28/2018 at 10:14
I have a 16" and 8".  Mine lost around 200 fps with super sonic loads to the shorter barrel.  You will likely be around 2100 to 2200 with 110s and your 8" barrel.   


-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: Rancid Coolaid
Date Posted: March/28/2018 at 10:40
Originally posted by supertool73 supertool73 wrote:

I have a 16" and 8".  Mine lost around 200 fps with super sonic loads to the shorter barrel.  You will likely be around 2100 to 2200 with 110s and your 8" barrel.   


...And it will be appreciably louder from an 8" than it was from a 16".


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Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.


Posted By: supertool73
Date Posted: March/28/2018 at 10:43
Indeed. The short barrels are crazy loud. 


-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: Tip69
Date Posted: March/28/2018 at 13:35
remind me what SBR is again please.....

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take em!


Posted By: supertool73
Date Posted: March/28/2018 at 13:43
Short barreled rifle.  Anything under a 16" barrel you have to pay a $200 tax and get permission from the ATF.


-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: Tip69
Date Posted: March/28/2018 at 16:47
thank you Sir

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take em!


Posted By: helo18
Date Posted: March/28/2018 at 18:13
Originally posted by Rancid Coolaid Rancid Coolaid wrote:

Originally posted by helo18 helo18 wrote:

I would curious as to which would be quieter.  I run a 10.5" 5.56 with a suppressor and it is still loud enough I like ear plugs.  I may build a short barrel 6.5 grendel just to see what happens.

What can are you using?
Are you shooting indoors or heavy woods/other structures?

At its core, short barrel is loud barrel.

I run a 10.5" SBR quite often and it is comfortable outside and in open spaces, but yea, gets uncomfortable in environments where sound can bounce around.  If you are using a 30-cal can on a 223, I have found them to be louder, even though they have higher volume.  This is anecdotal, no metered data to substantiate it. 

I am running the M4-2000 on the SBR.  If I went up to a bigger caliber, I would probably run my Specwar 762 on it.

I guess I have shot it in a few different venues.  Ranges, PD hunting, fields and woods.  All seems loud when shooting.  Standing 3 feet back when someone else shot wasn't bad at all.


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To be prepared for War is one of the most effectual means of preserving peace.

GEORGE WASHINGTON


Posted By: Lockjaw
Date Posted: March/29/2018 at 11:32
Mine is an 11.5 in 5.56, and to be honest, I can't tell much diff between it and a 16in one as far as noise. Both of them have the regular mil spec flash hider on them. 

Even when I shot it inside to get the red dot sighted in, I was expecting it to be way louder based upon what everyone here has said, and I didn't notice it either. With muffs on. 

I was shooting regular 55gr ammo. 


Posted By: Rancid Coolaid
Date Posted: March/29/2018 at 12:16
As I said, anecdotal.  Your anecdotes do not align with my anecdotes.

A shorter barrel means bigger fireball too.

My ARs, suppressed and unsuppressed, are appreciably louder as the barrels get shorter, same ammo, same can, same shooter observing.

Do you, Lockjaw, have any permanent hearing damage?


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Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.


Posted By: Kickboxer
Date Posted: March/29/2018 at 18:15

eehhh???  Whadesay???

Lockjaw:



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Opinion,untempered by fact,is ignorance.

There are some who do not fear death... for they are more afraid of not really living


Posted By: Urimaginaryfrnd
Date Posted: March/30/2018 at 20:22
.375 H&H

45-70 

well its the thought that counts Whistling  in an AR pistol length I like the 300 Blk but I've come to terms with the idea that sometimes its more important to have one ass stomping big heavy bullet than a whole herd of little ones. 


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"Always do the right thing, just because it is the right thing to do".
Bobby Paul Doherty
Texas Ranger


Posted By: koshkin
Date Posted: March/30/2018 at 20:37
458SOCOM is a nice SBR cartridge.

Ilya

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http://www.darklordofoptics.com - www.darklordofoptics.com
https://rumble.com/c/DLO - Rumble Video Channel


Posted By: Kickboxer
Date Posted: March/30/2018 at 21:49
It actually is.  Loses little velocity going from a 16 inch barrel to a 10.5 inch barrel.  I would like to try some 200 grain polycase out with that… I really like the polycase ammo.  I've been considering a SBR, if I can make one make sense to me… the .458 SOCOM is my number one candidate at this point in time.  
I think it will ROCK...


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Opinion,untempered by fact,is ignorance.

There are some who do not fear death... for they are more afraid of not really living


Posted By: supertool73
Date Posted: March/30/2018 at 21:53
.375 socom looks neat too

-------------
Lifetime warranty and excellent customer service don't mean a thing when your gun fails during a zombie attack.

"A Liberal is a person who will give away everything they don't own."


Posted By: Kickboxer
Date Posted: March/30/2018 at 22:11
Originally posted by supertool73 supertool73 wrote:

.375 socom looks neat too
I've heard some good things about that round, but have no experience with it.


-------------
Opinion,untempered by fact,is ignorance.

There are some who do not fear death... for they are more afraid of not really living


Posted By: koshkin
Date Posted: March/30/2018 at 22:44
A subsonic 600gr 458 Cal bullet would work really well in an SBR.

Ilya

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http://www.darklordofoptics.com - www.darklordofoptics.com
https://rumble.com/c/DLO - Rumble Video Channel


Posted By: Rancid Coolaid
Date Posted: March/31/2018 at 09:00
I have thought about 458 or 375 from an SBR, but neither would work with existing cans I own now.

My go to for subsonic is 220 gr 300BO. But yea, a 600gr chunk of lead would be ass-kicking.

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Freedom is something you take.
Respect is something you earn.
Equality is something you whine about not being given.


Posted By: koshkin
Date Posted: March/31/2018 at 10:08
My next subsonic will be Q's 8.6CM. it is a really interesting design.

Ilya

-------------
http://www.darklordofoptics.com - www.darklordofoptics.com
https://rumble.com/c/DLO - Rumble Video Channel



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