9mm Barrel Length?

[wahoo95]

What's the longest barrel one can have and consistantly expect to keep 147gr 9mm subsonic? I know most favor the 5" TROS, but what about the 7", 8", or even 10.5" barrels?

[RyanB]

I can't tell you what the longest barrel that will work is. But why, when the most you can gain without risking supersonic rounds is less than a hundred feet per second, there would be any benefit to a barrel longer than 5 inches? Its just dead weight and length.

[jcgfire33]

Go WAHOOS!! Seriously. If it matters, I finally got my NFA paperwork for my 9mm SBR with a YHM Cobra silencer. I've got a 7.5" barrell on a RRA upper and POF lower. I liked the way it felt with a 9" Daniel Defense Rail. I've fired a couple of different 147gr. ammo types and most all of them have been sub-sonic. Don't get me wrong, there is 147gr. ammo that will go supersonic in my 7.5" barrell. Winchester Ranger ammo in 147gr. will go supersonic. Good luck and God Bless