I'd have to agree with others here that using the Lee crimp die for most gas gun reloads is an; accuracy up grade in the first order. I can tell the difference in my M1A when I use the Lee F/D verse when I don't. As for the bolt rifle; well if I'm working on match ammo I don't use it… not to say it doesn't work, I just don't use it. As for hunting ammo in a bolt action of pump; sure'…, I use it all the time for that.
As for brass life; well look at a factory crimp round in your caliber…. you should be able to see the depth of their crimp, try to stay on that guide.
On a side note; I've use the Lee F/D on subsonic center fire load, which demand a very, very heavy crimp… about three to four times what your doing…. an case life is still very good.
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