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Old July 30, 2011, 09:33 AM   #2
Unclenick
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Join Date: March 4, 2005
Location: Ohio
Posts: 21,060
The stability calculator on the the JBM site suggests this bullet is likely to tumble at sea level. You can shoot a short flat base, like the Sierra semi-point (0.755" long) but your Nosler is 0.790" long according the site's length list, and that crosses a line in stability according to the calculator. It causes the prediction that it will be unstable and tumble and whiz off in all directions.

On the other hand, I find that calculator often estimates the numbers too low with .224" bullets. I don't know why. It does quite well with .308 diameters. So, the only thing you can do is try it and see. Watch for fully or partially sideways holes (keyholing) in the paper, assuming it lets you hit it at all. No way to be sure up front. You would have better certainty of stability using the Sierra bullet I mentioned.

Here's a result window for the calculation. Basically, the stability number is what is called a gyroscopic stability factor, and the bullet is just stable when the number is 1.0. Sierra recommends you have a bullet in the range of 1.3 to 3.0 for hunting accuracy. The match shooters say 1.4 to 1.7 is best for tack driving, with 1.5 being the most cited optimal figure.



I would use the H380 data Hodgdon lists for the 60 grain V-max. That is 37.5 grains to start and 40.5 grains maximum, with a COL of 2.350", in a Winchester case with a Winchester LR primer.
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