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Nathan · October 8, 2012, 08:03 PM

First, the ammo you measured is sized for a 223 rem chamber. Your rifle is a 5.56 chamber, it seems. In general, 0.002 - 0.003 is good. In bolt guns, I shoot for 0 to -0.002. In my AR, I like to see 0.002 - 0.005 in an FL die.

So, you are in the ballpark, IME, but don't forget that there is quite a bit of variation in FL sizing. Most of your variation is controlled by consistency of lubrication. Get inside the neck too. I often measure the first 10 and then like 1 in 25 to be sure I'm being consistent enough.

October 8, 2012, 08:03 PM	#3
Nathan Senior Member Join Date: July 1, 2001 Posts: 6,331	First, the ammo you measured is sized for a 223 rem chamber. Your rifle is a 5.56 chamber, it seems. In general, 0.002 - 0.003 is good. In bolt guns, I shoot for 0 to -0.002. In my AR, I like to see 0.002 - 0.005 in an FL die. So, you are in the ballpark, IME, but don't forget that there is quite a bit of variation in FL sizing. Most of your variation is controlled by consistency of lubrication. Get inside the neck too. I often measure the first 10 and then like 1 in 25 to be sure I'm being consistent enough.