How much MOA needed for a scope on a .308 to do 100yds shots?

[Lightload]

With 175s, you are going to need 38-40 MOA to get to 1000, maybe less but somewhere in that neighborhood. Your base rings combo might not match up well to center the reticle so any scope with only 25-40 MOA will not work

Recommend you add a 20 MOA base to help you center the reticle as a minimum.

Go with a 20moa base. If you go more than that, depending on the scope, you may have trouble zeroing at 100.

 

[Turbulent Turtle]

FWIW - most scopes will come from the manufacturer with the reticle optically centered; that is to say it will have available one half the total adjustment range in either direction (vertical or horizontal). For example, with the reticle optically centered, a scope that has 60 MOA total elevation adjustment will have approximately 30 MOA up and 30 MOA down travel. To zero at 100 yd, a typical .308 might need about 2 MOA to get a 100 yd zero. That means it now has only about 18 MOA upward travel remaining. With a 20 MOA base, it will be close to 38 MOA upward travel because the base gets back 20 MOA travel that would be lost (i.e. downward travel) without it. If it takes 38 MOA to reach 1000 yd, that scope with a 20 MOA base is really going to be pushing the limit of whether it will have enough adjustment. In addition, it is optically much better not to be at the very extreme limit of travel. A 30 MOA base might be better for a scope with 60 MOA total elevation adjustment, even if it hampers your ability to zero at 100 yd.

The above response is good except for a small computation problem. 30-2=28, not 18. The rest is off by 10 MOA.

 

[trhodes]

I plugged the question into iSterlok ballistics progrm and it predicted 38.9 moa. My assumptions were .308 win, 168 gr smk at 2650 fps. Yeah, 20 moa ramp would be needed ( for my setup).

 

[Turbulent Turtle]

trhodes; I predict a lot of good times ahead with that load at 1000 yards. You will develop a sense of amazement. The question is "why would anyone even consider that bullet for 1000 yards in a .308?"

gstaylorg; no worries. I never made such a mistake. This afternoon, I mean.

 

[XTR]

trhodes; I predict a lot of good times ahead with that load at 1000 yards. You will develop a sense of amazement. The question is "why would anyone even consider that bullet for 1000 yards in a .308?"

gstaylorg; no worries. I never made such a mistake. This afternoon, I mean.

What may be lost on you throdes, is that Denys is trying to tell you not to use that bullet.

I am personally trying to get BATF to actually do something useful and require that that bullet me marked with a warning similar to cigarettes something to the effect of "Caution, this bullet was developed for 300 yard shooting and has never been intended for any range beyond 600." Now that warning will probably work as well as the "not for hunting" warnings on various target bullets and will have to be followed up with. "Pay attention now, this bullet will tumble before it gets to 1000 yards when fired from a 308 with any load that does not border on insane, and even some that do."

 

[miamigunsinc]

You can buy a new LEUPOLD VX-3 6.5-20x50 Long Range Target Riflescope