Krieger 4groove or Bartlein 5R for 7STW build?

[Popapi]

Guys which would you go with and why. I'll be doing a build to shoot 140 to the 180VLDs.....also would you go with a 8.5 or 9 twist? Thanks for your advice!

 

[FearNoWind]

Bartlein 5R 9 twist ....
Shoots those 180 grain Berger VLDs like nothing else. Of course, the 8.5 wouldn't be an especially bad choice either - depending on your choice of bullets.

 

[FearNoWind]

Bartlein 5R with 9 twist ....
Shoots those 180 grain Berger VLDs and the 150 grain Barnes LRX like nothing else. Of course, the 8.5 wouldn't be an especially bad choice either - depending on your choice of bullets.

 

[MudRunner2005]

Gotta agree 100%. 26" or longer Bartlein 5R 9" twist.

If you plan to ever shoot the Berger 195 EOL's (when available) or Matrix 190's, I would go with the 8.5" twist.

 

[Popapi]

Was just wondering the guy at Kroger told me to consider a 8.5 for the 180s, but always been a fan of the Bartlein!

 

[Edd]

At sea level and 0°F, it takes an 8.5" twist to stabilize a 180 gr Berger.

 

[MudRunner2005]

At sea level and 0°F, it takes an 8.5" twist to stabilize a 180 gr Berger.

At 500' above sea level on a 40* day a 9.25" twist can spin a Berger 180 Hybrid in a 7mm STW....

Done it.....A BUNCH.

 

[Edd]

At 500' above sea level on a 40* day a 9.25" twist can spin a Berger 180 Hybrid in a 7mm STW....

Done it.....A BUNCH.

Spinning and properly stabilizing aren't the same thing. When someone asks for a recommendation, they deserve an accurate one. At 500' above sea level on a 40* day an 8.75" - 9.00" is about the minimum. You would need 3650 FPS to get to an SG of 1.5 with a 9.25" twist.

 

[Popapi]

So I can't go wrong with either for 180s on down right guys?

 

[MudRunner2005]

Spinning and properly stabilizing aren't the same thing. When someone asks for a recommendation, they deserve an accurate one. At 500' above sea level on a 40* day an 8.75" - 9.00" is about the minimum. You would need 3650 FPS to get to an SG of 1.5 with a 9.25" twist.

Oh you're right, I guess ragged hole groups doesn't matter either... I also never recommended anything.

Just because someone at Krieger says you need an 8.5 twist to stabilize a 180 means that everybody on here's personal experience doesn't mean squat?

 

[Edd]

Just because someone at Krieger says you need an 8.5 twist to stabilize a 180 means that everybody on here's personal experience doesn't mean squat?

You aren't "everybody" and the Berger calculator supports what someone at Krieger said.

Since there is no downside to using an 8.5" vs a 9" or a 9.25" , the better choice would be an 8.5"

 

[MudRunner2005]

You aren't "everybody" and the Berger calculator supports what someone at Krieger said.

Since there is no downside to using an 8.5" vs a 9" or a 9.25" , the better choice would be an 8.5"

You're right, but I'm also far from the only person shooting 180's in a 9.0-9.25"'twist with a positive outcome.

 

[WildRose]

If it were me and I was going to shoot the heavies I would go with an 8 or 8.5 twist. It doesn't cost any more to go with an 8 and it will not hurt your accuracy if you choose to shoot the lighter bullets as well.

 

[Pdvdh]

Yup. You can guess and take your chances, or you can calculate the proper twist rate using the best science available, and have much better odds of ending up with the twist rate that will stabilize your bullets at sea level in frigid temperatures, or at 10,000' elevation, in shirt sleeves.