300aac blackout 9inch barrel vs 16 inch barrel

Discussion about rifles in 300 AAC BLACKOUT (7.62x35mm), hosted by the creator of the cartridge.

Moderators: gds, bakerjw, renegade

dizle
Member
Posts: 24
Joined: Sun Jun 10, 2012 10:20 pm

300aac blackout 9inch barrel vs 16 inch barrel

Post by dizle » Mon Jun 11, 2012 3:28 am

so i have a 16 inch barreled 300blk ar, and i love it, but ive been reading that a 9 inch barrel can do the same as a 16 inch, is that true?
will a 9inch barrel be as accurate as a 16inch barrel(shooting the same ammo) at 100 yards? 200 yards? 300 yards? 400 yards?
does it create the same energy at those ranges?
same energy lost and bullet drop at same ranges?
same velocitys?

what are the advantages of a 16inch barrel vs a 9 inch barrel?

sorry if this is a repeat post but im new here and quite curious........

BulletFlight for Android
follybeacher
Silent Operator
Posts: 80
Joined: Thu Sep 22, 2011 8:30 am

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by follybeacher » Mon Jun 11, 2012 10:02 am

i own a 16" and love it. i'm in the same boat as you and want a sbr. so watch this video as i found it very enlightening:

http://www.youtube.com/watch?v=hLqmw-c6kcU

User avatar
300Blk
Site Admin
Posts: 7330
Joined: Mon Apr 25, 2005 9:31 am
Location: USA

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by 300Blk » Mon Jun 11, 2012 12:01 pm

The 16 inch has both more velocity and more accuracy, but the difference in velocity is less than most other cartridges.

jason
Silent But Deadly
Posts: 194
Joined: Fri Feb 03, 2012 3:27 pm

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by jason » Mon Jun 11, 2012 1:42 pm

I noticed that my 175gr subsonics (in my 9") become supersonics in my 16".
One of these weekends I'll do a chrono run with both guns.

Turnpike
Member
Posts: 23
Joined: Fri Sep 04, 2009 12:31 am

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by Turnpike » Mon Jun 11, 2012 9:12 pm

I am running a 9" AAC Upper on my rifle. I believe a similar powder charge and similar factory ammunition shows me at about 200 fps less than the posted results of a 16" barrel. I am only using my memory to recall this. I hope to have my father's CMMG Blackout up and running to see what difference exsisted between those two (the only ones I have available to me).

Mike

BC98
Senior Silent Operator
Posts: 148
Joined: Fri Dec 07, 2007 9:59 pm
Location: Twin Cities, MN

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by BC98 » Tue Jun 12, 2012 11:21 am

I've chrono'ed the same factory Remington rounds through a 9" and a 16" barrel (both AAC uppers) and the velocity difference was 160 fps on the day I tested. Ammo was the 125gr Premier.

robrob
Silent But Deadly
Posts: 302
Joined: Wed Nov 25, 2009 9:53 am
Location: West Virginia

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by robrob » Tue Jun 12, 2012 1:42 pm

A 16 inch barrel will make very little difference in accuracy for subsonic rounds but supersonic rounds will normally be more accurate and faster (shooting slightly flatter) but the extra length, weight and loss of cool factor have to be compared to the 9 inch SBR and tax stamp pain.

Silverback
Member
Posts: 10
Joined: Thu Mar 16, 2017 7:56 am

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by Silverback » Sat Mar 14, 2020 4:07 pm

I am new to 300 blackout so hopefully you wont mind me jumping in on old posts.

I was thinking about a 10.5 barrel build until I viewed the attached video.

I like the idea of getting the most of a cartridge and it seems that the 16 inch barrel continually sends more energy down range.

Now I am ok with giving up some energy for mobility.
For instance I use a 16 inch .223


Any input or advice welcome.

https://youtu.be/4VNl7QXykUY

User avatar
bangbangping
Silent But Deadly
Posts: 2609
Joined: Sun Sep 15, 2013 6:34 pm
Location: Texas Gulf Coast

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by bangbangping » Sat Mar 14, 2020 9:32 pm

Silverback wrote:
Sat Mar 14, 2020 4:07 pm
I am new to 300 blackout so hopefully you wont mind me jumping in on old posts.

I was thinking about a 10.5 barrel build until I viewed the attached video.

I like the idea of getting the most of a cartridge and it seems that the 16 inch barrel continually sends more energy down range.

Now I am ok with giving up some energy for mobility.
For instance I use a 16 inch .223


Any input or advice welcome.

https://youtu.be/4VNl7QXykUY
Everything is a compromise, and it all depends on what your goals are and what you want to do with it.
Do you plan to hunt with it? If so, what and what distances?
Sub? Super? Both? Suppressed?
Do you reload or plan to shoot only factory ammo?

Personally, I've had a bunch of barrel lengths. I still have a 16" bolt gun when I want to maximize velocity (20" would be better), but have settled on 11"-12" as a great compromise for both sub and super with a suppressor. By 12" you've gained a large chunk of the potential velocity, and it can be much quieter shooting subs than an 8"-9" barrel.

If you don't plan to run a suppressor, go as long as possible. Short barrels unsuppressed are obnoxious. :twisted:

Silverback
Member
Posts: 10
Joined: Thu Mar 16, 2017 7:56 am

Re: 300aac blackout 9inch barrel vs 16 inch barrel

Post by Silverback » Sat Mar 14, 2020 10:19 pm

Planning on reloading shooting 110 or124 grain and 220 grain. Going to eventually pick up supressor.

I just hate wasting that energy potential.

Would a 16 inch barrel be fine for super and supressed?

Post Reply