School me on pros and cons of 10.5 vs 11.5" ARs

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[ARCHIVED THREAD] - School me on pros and cons of 10.5 vs 11.5" ARs

Posted: 12/9/2013 8:32:39 PM EDT

So I've decided to build a SBR (pistol for now) with at least a 10 inch barrel to host my pending Saker. While I enjoy shooting my 7.5 inch pistol, I won't be able to run the Saker on it. I remember that there are some key ballistic/gas issues with the 10-12inch range ARs, but I can't recall the specifics. The suppressor will probably live on this gun and won't see very many unsuppressed rounds, but will I need an adjustable gas block to ensure that if functions both ways?

I'd like to keep it as short as possible given that the can will be on it a lot, but if it's significantly better in terms of ballistics to go with an 11.5", then I can live with it being an inch longer. So what are y'all running and why?

Posted: 12/9/2013 10:34:11 PM EDT

[#1]

One single inch will make next to no difference.

Posted: 12/9/2013 10:52:43 PM EDT

[#2]

Link

Posted: 12/10/2013 12:20:28 AM EDT

[#3]

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One single inch will make next to no difference.

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It can make ALL the difference. See link above.

Posted: 12/10/2013 5:48:41 AM EDT

[#4]

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Some good information in that thread.
My take away is that for suppressed running it can make a HUGE difference but for non-suppressed "normal" running it is less of an issue.
Either way, I recently ordered an 11.5" barrel from ICE arms and planning to run it on an AR Pistol that will be non-suppressed.

Posted: 12/10/2013 6:04:42 AM EDT

[#5]

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That link is about dwell time and reliability of cycling the rifle. Both 10.5 and 11.5 can run well if properly tuned. Period. Get what you want and build it well. Seems to me that a shorter length barrel can be tuned by proper gas port size and type of spring you put in the buffer tube to allow less resistance to cycling while not over taxing the internal parts.

Posted: 12/10/2013 7:10:47 AM EDT

[#6]

10 or 11.5 plus suppressor equals a normal length gun...just use it as such...It wont be any more maneuverable that a 16er

I suppose its just my oppinion if you wanna get the real benefits of a shorty its gotta be 7.5...even with a suppressor on that you will loose alot of its ability, but if you need to be quieter you need it.

Anyone who says its just a novelty gun in that size has not done the due diligence to find the proper loads to make it most useful in that size for any given duty...I highly doubt those same people would want to step in front of the muzzle at even 500yds of a 7.5 pistol/sbr

I have never taken my pistols to 500yds...but I have shot out to 300m...and she was dinging steel as authoritatively as any other gun I was shooting that day.

Posted: 12/10/2013 8:14:36 AM EDT

[#7]

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Quoted:
10 or 11.5 plus suppressor equals a normal length gun...just use it as such...It wont be any more maneuverable that a 16er

I suppose its just my oppinion if you wanna get the real benefits of a shorty its gotta be 7.5...even with a suppressor on that you will loose alot of its ability, but if you need to be quieter you need it.

Anyone who says its just a novelty gun in that size has not done the due diligence to find the proper loads to make it most useful in that size for any given duty...I highly doubt those same people would want to step in front of the muzzle at even 500yds of a 7.5 pistol/sbr

I have never taken my pistols to 500yds...but I have shot out to 300m...and she was dinging steel as authoritatively as any other gun I was shooting that day.

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Name me one suppressor manufacturer that will warranty their suppressor on a 7.5" 5.56 as it isn't going to happen.

Posted: 12/10/2013 8:18:59 AM EDT

[#8]

Quoted:

Name me one suppressor manufacturer that will warranty their suppressor on a 7.5" 5.56 as it isn't going to happen.

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Sure, AAC

http://www.advanced-armament.com/Warranty-Information_ep_50-1.html

762-SDN-6 and SR7 warranted on barrels as short as 7.5” when used with 300 AAC BLACKOUT or 5.56mm.

Posted: 12/10/2013 8:41:06 AM EDT

[#9]

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Sure, AAC

http://www.advanced-armament.com/Warranty-Information_ep_50-1.html

762-SDN-6 and SR7 warranted on barrels as short as 7.5” when used with 300 AAC BLACKOUT or 5.56mm.

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Quoted:

Quoted:

Name me one suppressor manufacturer that will warranty their suppressor on a 7.5" 5.56 as it isn't going to happen.

Sure, AAC

http://www.advanced-armament.com/Warranty-Information_ep_50-1.html

762-SDN-6 and SR7 warranted on barrels as short as 7.5” when used with 300 AAC BLACKOUT or 5.56mm.

This guy broke the '13er curse. He knows his stuff.

Posted: 12/10/2013 9:05:46 AM EDT

[#10]

http://www.ar15.com/forums/t_6_20/405331_Suppressor_for_a_7_5_sbr.html

Saker does as well and a few others according to this post.

Posted: 12/11/2013 7:21:30 AM EDT

[#11]

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Quoted:

This guy broke the '13er curse. He knows his stuff.

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Quoted:

Quoted:

Name me one suppressor manufacturer that will warranty their suppressor on a 7.5" 5.56 as it isn't going to happen.

Sure, AAC

http://www.advanced-armament.com/Warranty-Information_ep_50-1.html

762-SDN-6 and SR7 warranted on barrels as short as 7.5” when used with 300 AAC BLACKOUT or 5.56mm.

This guy broke the '13er curse. He knows his stuff.

Nice!

Posted: 12/11/2013 8:09:02 AM EDT

[#12]

10.5." I've read up on all the reasons why the 11.5" is superior (mainly dwell time), but I figure 10.5" has been around for long enough and used by some pretty serious folks, so it can't be all bad. Mine has been 100% from the start with all types of crappy ammo. It was tamed a bit with a full profile carrier and an H3 buffer as it was a bit of a jackhammer. In the current state it is just as smooth as my rifle length dissipator.

They have a reputation for being finicky, but as with all short barrel builds, have the extractor upgrade parts to start out with (heavy duty spring and/or O-ring). Pick a buffer weight that works both suppressed and unsuppressed.