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Posted: 6/12/2008 10:22:42 AM EDT
| can i shoot 75 grain ammo accurately in my 1/9 rra upper |
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Here's a handy reference from ATK. I measured a 'T1C' version of the 75gr Hornady at .982". Per the chart 1:8 will marginally work and 1:7 would be better. http://le.atk.com/pdf/223_MinimumTwistRates.pdf My partner's 1:9 bushy won't group 75gr 5.56mm TAP very well at all. My 1:7 LE6920 put 5 shots into ~0.6" at 50meters using an ACOG. |
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