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Post by bloodhound on May 29, 2009 17:44:12 GMT -5
WHAT TWIST WOULD YOU GO WITH IN A 445 SUPER MAG....SHOOTING 240 GR JSP.....MAYBE UP TO 300 GR BULLETS....
ON A SIDE NOTE I READ THAT FREEDOM ARMS IS USING A 1 IN 24 TWIST IN THEIR 44 MAGS.....THANKS FOR YOUR THOUGHTS.... ;D
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Post by nobearsyet on May 30, 2009 10:11:41 GMT -5
Bloodhound, let me know how long the bullets you want ot shoot are and I'll do the math and tell you what's ideal
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Post by AxeHandle on May 30, 2009 10:31:48 GMT -5
Thoughts? We have people here who actually think? ;D You want me to pull out the Gallagher 445 and a cleaning rod and tell you what he uses don't you....  Maybe later today... The honey do list is killing me!  |
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Post by nobearsyet on May 30, 2009 10:32:45 GMT -5
I was just going to plug it inot the greenhill formula
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Post by bloodhound on May 30, 2009 16:10:36 GMT -5
NOBEARSYET....
240 GR BULETS ARE .695" LONG
300 GR BULLETS ARE .871" LONG.....
PLEASE POST THE FORMULA....THANKS.... ;D
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Post by AxeHandle on May 30, 2009 16:56:39 GMT -5
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Post by bloodhound on May 30, 2009 19:59:30 GMT -5
AXE...I DID A SEARCH....AND ALSO FOUND THAT SITE....
I'M FINDING A 1 IN 20" FOR ALL BULLET WEIGHTS...
ANOTHER CHOICE IS 1 IN 16"...
I'M LEANING TOWARDS A SHILEN STAINLESS WITH 1 IN 20"....
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Post by nobearsyet on May 30, 2009 21:38:50 GMT -5
Z-Hats file wouldn't open on this computer, but the formula is T=150(d/r) where T=twist rate, d is the bullet diameter, anr r is bullet diameter ratio (the bullet length divided by it's diameter) use 180 instead of 150 for cartridges that exceed 2800fps. as an example your 300grn bullet is .871 long, and we can assume a diameter of 429(standard if I'm not mistaken but size for your chamber throats for best accuracy) so .871/.429=2.03(rounded) so 31.69 (your optimal twist rate for that bullet=150(.429/2.03) hope this helps and you can do it with any bullet
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