300Blk pistol barrel length suggestions

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[ARCHIVED THREAD] - 300Blk pistol barrel length suggestions

Posted: 8/23/2017 10:47:22 AM EDT

What would you say is the optimal barrel length for 300Blk pistol in terms of compactness, reliability and sufficient velocity for factory 100-120gr JHP bullet?
I was thinking of 8 1/2" but not sure as my only 300Blk is a carbine with 16" barrel.

Posted: 8/23/2017 11:54:26 AM EDT

[#1]

An 8.5" barrel completely burns the powder in the cartridge...
You only pick up about 100-120fps going from 8.5" to 10.5".
In PA, to carry loaded in a vehicle, said pistol needs to be under 26" OAL (not including attachments like suppressors), so I chose 8.5" to stay safely under 26" without having to go piston or short tube route.

Posted: 8/23/2017 12:36:34 PM EDT

[#2]

Quote History

Quoted:
An 8.5" barrel completely burns the powder in the cartridge...
You only pick up about 100-120fps going from 8.5" to 10.5".
In PA, to carry loaded in a vehicle, said pistol needs to be under 26" OAL (not including attachments like suppressors), so I chose 8.5" to stay safely under 26" without having to go piston or short tube route.

View Quote

Would that be with both subsonic and supersonic?

Posted: 8/23/2017 1:13:03 PM EDT

[#3]

Quote History

Quoted:

Would that be with both subsonic and supersonic?

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You will see less muzzle velocity difference when using subs. The 100-120fps loss is with supers.

Posted: 8/23/2017 1:40:28 PM EDT

[#4]

8.5" gtg

Posted: 8/23/2017 2:35:54 PM EDT

[#5]

8.5 inch

Posted: 8/23/2017 6:43:50 PM EDT

[#6]

Quote History

Quoted:
8.5 inch

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Good deals to be had for 8.5". Shop around.

Posted: 8/23/2017 7:01:48 PM EDT

[#7]

Thanks for all your replies.
I guess 8 1/2" is the way to go.

Posted: 8/23/2017 9:29:13 PM EDT

[#8]

Going against popular opinion, 8".

Posted: 8/23/2017 9:54:59 PM EDT

[#9]

Quote History

Quoted:
Going against popular opinion, 8".

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The 8 is Great.

Posted: 8/24/2017 12:33:19 AM EDT

[#10]

I thought it had complete powder burn in 9 inches?

Posted: 8/24/2017 1:23:30 AM EDT

[#11]

8-10" is probably optimal. I get 2066fps average out Barnes 110gr black tip out of an 8.5" barrel, compared to 14.5" barrel same bullet I get 2230fps. So for 6" of barrel I gain about 164fps, or 27fps per inch

Posted: 8/24/2017 11:42:12 AM EDT

[#12]

From the people who developed the 300BO, it appears the 9" is the optimal barrel length for supers and subs. That is not to say that a small, very small, gain isn't possible with certain types of ammo with variations in barrel length, but the originators intended 9" to be optimal. Slight variations either side of that will probably perform just fine. I use a 9.5" barrel for my subsonic blackout, and a carbine gas 16" for supers. I reload. I can take advantage of small advantages in the 16" in this way, but if I could only have one to shoot both it would be my 9.5".

Posted: 8/24/2017 3:55:14 PM EDT

[#13]

This right here is your jam.

http://ballisticadvantage.com/8-3-inch-300-blackout-hanson-pistol-performance-barrel.html

Posted: 8/25/2017 1:08:58 AM EDT

[#14]

10" for me

Posted: 8/25/2017 1:13:44 AM EDT

[#15]

I went 8", but it's designed for 9" for optimal performance. Unless you're shooting super sonic ammo, you won't get anything extra from a longer barrel. With supers you will get a little more velocity, but not a lot more even with a 16" barrel. This caliber is really designed for subsonic ammo though.

[ARCHIVED THREAD] - 300Blk pistol barrel length suggestions

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