9 og. 30 cal bullet question

B

Bill Whitener

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I am currently shooting Score , with a 17 twist Bartlein barrel - with 7 ogive - 116 grain bullets and it works really good. Just to have something to do - we have a 9 og. point up die coming from Niemi. He said we should get 1 in. jackets to make 120 to 125 bullets. Now what twist barrel will shoot best with this bullet . Thanks
 
I could give a guess, but best would be to make contat with R. G. Robinett

http://www.bibullets.com/

He has the skill to both give you a theoretical answer, and with all the short .30s he's made over the years, practical results as well. R.G. started as a Hunter score shooter long ago, and it wouldn't surprise me if he hasn't made .30s on every jacket ever offered.
 
Your 17 twist should be fine in weather of normal temperatures. Colder temps will give questionable results. 18 will also work with the heavier bullets, but light bullets may give questionable results. These answers apply to 1 in jackets.
 
Some will probably disagree but a few of us are using a 16 twist barrel. We are using 8 og bullets with great results.
Same loads as with the 17 twist s
 
Bill, I have shot Randy's 118 BIB 10 ogive, on one inch jackets in my 1-18 with no ill affects. But, to be on the safe side, a 1-17 might be the logical choice for a 1 inch jacket bullet.

I bet Randy will tell you to heck with it, go with the 1-18........jackie
 
Bill Whitener said:
I am currently shooting Score , with a 17 twist Bartlein barrel - with 7 ogive - 116 grain bullets and it works really good. Just to have something to do - we have a 9 og. point up die coming from Niemi. He said we should get 1 in. jackets to make 120 to 125 bullets. Now what twist barrel will shoot best with this bullet . Thanks
Click to expand...

The 1:17" twist will handle any FB bullet, up to 1.100" long - with bullets of this length, and sea-level/Std. conditions, Sg will exceed 1.4. With 1.00" long jackets, a 17" twist will impart Sg upwards of 1.7.:cool: Counter-intuitively, a "pointier" bullet - of equal length - will have a HIGHER Sg than its more blunt-nosed counter-part. In short, for any bullet based upon a 1.00" long jacket, the 17" twist provides a HUGE [stability] safety net . . . and, relative to CG off-set/spin-rate (probable group size), no measurable down-side. :eek::D RG
 
thanks to everyone responding, The barrel I have is good, Bill
 
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