9mm Twist rate

[Stape]

Searching for an aftermarket barrel for a G19, I see some barrels with a twist of 1/9 while others are 1/16. I'm very familiar with twist rates for rifles and understand them and their application, but not so much with pistol calibers as I've never tried variations and gauged their performance with different ammo. So, by logical sense, I'd imagine the faster twist will stabilize heavier bullets. I run primarily 115gr handloads for general plinking, but am I going to keyhole targets with a 1/16 twist running 147's?

 

[67ray]

 

[Stape]

Uh oh, is this one of "those" topics? I've never heard it argued before. For my case, I simply want a stainless barrel for my G19. I found a Swenson for $67.

 

[PappyM3]

Searching for an aftermarket barrel for a G19, I see some barrels with a twist of 1/9 while others are 1/16. I'm very familiar with twist rates for rifles and understand them and their application, but not so much with pistol calibers as I've never tried variations and gauged their performance with different ammo. So, by logical sense, I'd imagine the faster twist will stabilize heavier bullets. I run primarily 115gr handloads for general plinking, but am I going to keyhole targets with a 1/16 twist running 147's?

Require twist is less about weight and more about the length of the bullet. 9mm bullets are short, very short. A 147gr is 0.574”. Rifle bullets are often over 1”.

A 147gr bullet fired from a 1-16 twist barrel at 900fps is stable.

 

[Stape]

Require twist is less about weight and more about the length of the bullet. 9mm bullets are short, very short. A 147gr is 0.574”. Rifle bullets are often over 1”.

A 147gr bullet fired from a 1-16 twist barrel at 900fps is stable.
View attachment 845271

Thank you very much. I have no idea what that is from, what program or whatever but looks good to me.

 

[highlander]

38 Super use the same bullets and uses a 1 in 16 twist rather than 1 in 9/10.

 

[PappyM3]

Thank you very much. I have no idea what that is from, what program or whatever but looks good to me.

There are a few different bullet stability calculators online if you do a search. I used the Berger bullets one, but a company called Bison has one too if I recall.

 

[Stape]

There are a few different bullet stability calculators online if you do a search. I used the Berger bullets one, but a company called Bison has one too if I recall.

Good to know. Thanks for the info, that's very helpful.

 

[Dennis in MA]

I want my 9's to tumble, yo.

 

[PappyM3]

I want my 9's to tumble, yo.

Blow BOTH lungs out.

 

[Mark from MA]

I want my 9's to tumble, yo.

Hold the gun sideways bro.....