The Firing Line Forums - View Single Post - practical purpose for .38 spl guns gone....

stinkeypete · April 18, 2019, 04:55 PM

Reply to the bad science posted in Reply 75:

The experimental bias of the longer barrel for the .357 is simply inexcusable. Shoot .38 out of the 2 1/2 .357 magnum gun? What happened to the 1 7/8" barrel?

Someone did some actual science properly:
http://ballisticsbytheinch.com/357mag.htmlhttp://

You can see that going from 3" to 2" drops .357 velocity by 200-300 fps depending on the factory ammunition. (Powder speed, I speculate)

Okay.. now I have a bee in my bonnet and am going to do a regression to see what the velocity difference simply due to barrel length would be...

assumption... velocity= 665 + 533 ln(Length) (not a bad fit and I don't care to muck about as we are spitballing)

Simply due to barrel length alone the velocity of Corbon 125 g ammunition would be 1153 fps at 2.5" and 1,000 fps (huh, nice round number) at 1.875"

The .357 magnum loses 153 fps simply due to barrel length.

SO... if we take barrel length in to account, your youtube guy would have gained...

150 FPS for a massive increase in recoil. I buy that. Complete agreement.

When you reduce powder, the velocity lost per barrel-inch is less...
http://ballisticsbytheinch.com/38special.html#RW

So you kill your zombie deader than mine.. but he was already ...dead.

April 18, 2019, 04:55 PM	#78
stinkeypete Senior Member Join Date: July 22, 2010 Location: Madison, Wisconsin Posts: 1,293	Reply to the bad science posted in Reply 75: The experimental bias of the longer barrel for the .357 is simply inexcusable. Shoot .38 out of the 2 1/2 .357 magnum gun? What happened to the 1 7/8" barrel? Someone did some actual science properly: http://ballisticsbytheinch.com/357mag.htmlhttp:// You can see that going from 3" to 2" drops .357 velocity by 200-300 fps depending on the factory ammunition. (Powder speed, I speculate) Okay.. now I have a bee in my bonnet and am going to do a regression to see what the velocity difference simply due to barrel length would be... assumption... velocity= 665 + 533 ln(Length) (not a bad fit and I don't care to muck about as we are spitballing) Simply due to barrel length alone the velocity of Corbon 125 g ammunition would be 1153 fps at 2.5" and 1,000 fps (huh, nice round number) at 1.875" The .357 magnum loses 153 fps simply due to barrel length. SO... if we take barrel length in to account, your youtube guy would have gained... 150 FPS for a massive increase in recoil. I buy that. Complete agreement. When you reduce powder, the velocity lost per barrel-inch is less... http://ballisticsbytheinch.com/38special.html#RW So you kill your zombie deader than mine.. but he was already ...dead. Last edited by stinkeypete; April 18, 2019 at 05:56 PM.