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tropicmaster
10-19-2009, 09:22 PM
Just getting started and dont have reloader yet. I am shooting a 600 yd match this weekend, and will have to do it with factory. I will be shooting the .308 federal GMM 175gr. Does anybody know the MV of this facory load so I can figure my drops and windages ? Also I was playing around on the JBM calculator. The point blank ranges seem pretty optimistic. Does anybody know what they use for that? I have for years thought that PBR was the distance that a round deviates no more than 3" from line of sight. They are showing a PBR for the .308 of 350 yds. Aint no way for a 3" deviation is there?

dcloco
10-19-2009, 09:42 PM
Try here:

http://www.snipercentral.com/308.htm

Der Verge
10-19-2009, 10:08 PM
MV will have to be measured out of your barrel. Though the numbers they give are a good average of many rifles, you could have a rifle that could be shooting considerably outside that range. If so, a standard drop chart will do you no good. If your targets are only going to be at 600, as long as you are able to zero before the match, your MV will, for the most part, be non important. 2600 FPS is the advertised velocity.

As for MPBR (maximum point blank range), the "standard" or one you hear most of is 3", but this can change. Change mostly comes from the hunt of different animals. A MPBR of 3" is a bit obsessive when hunting moose, but rediculiously large for prarie dog. For the load you are speaking, I would be guessing they are talking about a 5" or 6" MPBR

savageboy
10-19-2009, 10:11 PM
Adam,

Sight in so you are 15" high at 100yds and you will be in the black somewhere at 600.

Der Verge
10-19-2009, 10:12 PM
Just for an Idea....
Range (yards) Muzzle 100 200 300 600
(200 yd. zero) -1.5 2.2 0.0 -9.0 -89.4
Wind Drift (inches) 0.0 0.7 2.9 6.9 31.2
Come Up in MOA -1.5 -2.1 0.0 2.9 14.2

JCalhoun
10-19-2009, 10:25 PM
Typical .308Win will use around 15 moa at 600y from a 100y zero. You will probably use 36 to 42 moa for 1000y from a 100y zero.