Trying some actual stability tests on some heavy 195-200 gn. cast in a 1-10 twist bbl. So I'm looking for some data .
I'm thinking 6.5 -7.5 Unique, or 231, maybe 12-15 gn 4227 or 4759 ????
This will be out of a 14" T/C contender
Trying some actual stability tests on some heavy 195-200 gn. cast in a 1-10 twist bbl. So I'm looking for some data .
I'm thinking 6.5 -7.5 Unique, or 231, maybe 12-15 gn 4227 or 4759 ????
This will be out of a 14" T/C contender
IHMSA # 566 "time sure flies when you're having FUN"
So lets take this from the start:
How long is your boolit?
If i substitute a Lee then 1.1" is max length.
Unique 7.5gr = 1521psi 1135fps
Win 231 7.5gr = 1590psi 1088fps
4227 15gr = 1254psi 1309fps (no clean burn!)
4759 is a no go in my old QL 2.9 sorry
So stability for a 1.1" boolit weighing 200gr launched at 1050fps from a 1/10 twist will yeald a stability factor of 3.39
Unless it's for subsonic then youre scraping the bottom of the barrel.
13.0 gr 4759 should get you in the range you want.
Here is a really great Low Velocity site. It only has 170 gr bullets for 30/30 but, you can work for that.
http://www.gmdr.com/lever/lowveldata.htm
Frank
311365 ia 1.257" and 311299 is 1.195"
JBM gives the 311365 @ 1100 a 1.99 factor and the 311299 a 2.26 factor Both in the green zone
Sierra/Miller program lists 1.4 th 2.0 as acceptable factors, the 311365 gets a 2.06 and the 311299 is even higher, So thats why I want "real shooting" to see what is what
Last edited by Wayne S; 07-31-2011 at 10:23 PM.
IHMSA # 566 "time sure flies when you're having FUN"
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