Sub 2000 question

Lokpyrite · November 1, 2011, 09:50 AM

Hello Folks, would a 147 grain 9mm still be subsonic when fired from a 16 inch barrel?

black mamba · November 1, 2011, 12:20 PM

Most likely not, but it's sort of borderline. Pistol rounds usually add about 20 fps per inch of barrel length up to 18" or so. That would put your 147 grainer at between 1050 and 1200 fps, depending on the load. You would have to chronograph it to be sure.

kozak6 · November 1, 2011, 11:01 PM

Look here:
http://www.ballisticsbytheinch.com/9mmluger.html

Quote:

it's sort of borderline

Exactly. The speed of sound is somewhere around 1100 fps depending on conditions, and a 16" barrel just about puts it there.

November 1, 2011, 09:50 AM	#1
Lokpyrite Senior Member Join Date: November 12, 2009 Posts: 367	Sub 2000 question Hello Folks, would a 147 grain 9mm still be subsonic when fired from a 16 inch barrel? __________________ The more people I meet the more I'm beginning to root for the zombies.

November 1, 2011, 12:20 PM	#2
black mamba Senior Member Join Date: September 13, 2011 Location: SW Florida Posts: 890	Most likely not, but it's sort of borderline. Pistol rounds usually add about 20 fps per inch of barrel length up to 18" or so. That would put your 147 grainer at between 1050 and 1200 fps, depending on the load. You would have to chronograph it to be sure.