I have a 5" on my AR SBR. 147s stay subsonic and I was shooting 124 ball and did not hear sonic cracks. I did not use my chrono so I can't tell you exact FPS readings. As for stabilizing, all shot well and using my Eotech sight and firing relatively quickly I was lobbing rounds into 4-5 inches...

I might add that you should be careful when using factory 9mm ammo. Some of the factory powder used is very abrasive and if it's not burnt very quickly in a short barrel can cause blast baffle wear. WWB used to be notorious for this. Since I reload, I haven't kept current on it. Also IME, 5-6"...

John A. wrote:

Greenmancgn wrote: Video is down

Sorry, maybe this will work.

https://www.youtube.com/watch?v=iLnNKeCCTh0

It did thank you

The Isreali's used a 10.5" barrel on their uzi's, and they had to go with 158 gr bullets to keep them subsonic. 147's would go super sometimes. So, that being part of my reason for liking barrels that are around 8.5 inches for 9mm. This gives more room for achieving full powder burn, while not...

To be more specific , I was looking to see if there was a standard barrel length that would allow for a good marriage between stabilization and ability to keep the projectile subsonic . Reading a bit more online I see that there are a few factors that come into play. I will eventually reload my own ...

doubloon wrote:By optimal you mean the longest barrel possible where things will remain subsonic?

Not optimal like 22lr where once the barrel is too long the bullet starts coasting?

http://www.ballisticsbytheinch.com/9luger.html

Yes subsonic , Thank you

So maybe my google-fu is weak but I cannot find a answer for best length for projectile stabilization and effective length for powder burn. Projectile will be factory load federal 147 gr FMJ (wadcutters) . I have read everything from 4.5 to 10 inches . Is there a chart or a site that can educate me ...