Twist rate and bullet stability at 900 yards

[dwm]

Darryl, do you think a 7mm RUM (28 in barrel) with an 11 twist would be able to stablize a 180 grain Berger?

Len, how long is the barrel on the 7mm Dakota? What is the Dakota case capacity? Is it between the WSM and RUM?

Doug

 

[Darryl Cassel]

DWM

I think you would need the 9 twist for the 180 gr.
That's the twists I have had in all my 7mm 30" barreled longrange hunting rifles.

later
DC

 

[dbhostler]

Darryl,

I have some 180 JLKs, would these stablize in a 9.5 twist in my Sendero?

db

 

[Len Backus]

DWM

Length is 32

77 grains of H1000 with the Cauterucio 176, don't know the case capacity.

 

[Darryl Cassel]

Hostler

I would think they would. Give them a try if you have them on hand.
My 180gr and 186gr did in a 30" barrel

Later
DC

 

[dbhostler]

Thanks, I'll give them a shot, sorry about that.

db

 

[Darryl Cassel]

Len

If your after high BC, look at the 180 Gr Berger or the 180 gr JLK.

This might just be the answer for you.
Their BCs were in the .7 range.

I had some 187gr 7mm Cattarucios years ago that really held up well at extended range in my 7/300 Weatherbys.
Same jackets as the Sierra MK.

You don't need excessive speed with a 180 gr plus grain 7 mm match style bullet.
Later
DC

PS---If I had a 7mm RUM or the 7mm/378 Weatherby, the 180 gr bullet would be my main bullet of choice.

[ 10-26-2003: Message edited by: Darryl Cassel ]