wondering what range anybody thinks is best to sight in a .300 win mag with a 26" barrel?usually shoot a 30-06 sighted it in at 100 yards.i've told to sight in 2"high at 100 yards to be dead on at 300 yards.bullet of choice is 180 grain swift scirocco.thanks in advance.

She won't shoot that flat. Run the numbers through the Beartooth External Ballistics Calculator and see what you get. Leave muzzle velocity at 3000 fps and B.C. at 0.5, if you don't know your exact numbers.
http://www.beartoothbullets.com/rescources/calculators/balistics/index.htm

Bye
Jack

wondering what range anybody thinks is best to sight in a .300 win mag with a 26" barrel?usually shoot a 30-06 sighted it in at 100 yards.i've told to sight in 2"high at 100 yards to be dead on at 300 yards.bullet of choice is 180 grain swift scirocco.thanks in advance.

Typically, from my own personal experience, using a .270win or a .30-06, either with about a 130 to 150 grain bullet... somewhere from 1.5" to 2" high at 100 yards gives you a dead on shot at ~200 yards... and you're anywhere from 6.5" to 8" low at 300 yards. Things really go downhill from there, no pun intended... bullet drop at 400 and 500 yards gets to be anywhere from just over 3 feet to almost 4 feet....

Anyway, whatever bullets you're using, you should be able to get a close estimate if you can find your muzzle velocity, balistic coefficient, and bullet weight. Like Jack said, find some sort of external balistics program and punch in the numbers.

But, just for kicks, do you happen to know what bullets you plan on shooting? Or if you already have them, can you tell us? If they are federal premium or remington, there are balistics charts available from their websites. If you're shooting Hornady, they usually have a sticker on the box that tells you what the bullet drop is if you zero for a given range. Other ammunition may or may not have readily available info, but more than likely you can find something close enough for hunting purposes...

Been doing the three inch at a hundred thing for all the high velocity hunting rifles for about 50 years now. Seems to work good for most rifles out to 300-350 yards. doesn't matter if it is a 270, 280, 300 mag or my ol 8 mag.

Keep in mind that here in Idaho you will get presented with a long cross canyon shot once in a while. If your a heavy brush type of hunter the plus 2 inch zero might be better

Like Jack says there is a Ballistics Calculator available on this forum use it. You will find that your not shooting as flat as you think at three hundred yards. http://www.beartoothbullets.com/rescources/calculators/balistics/index.htm