Need help calculating how high to sight bullet at 100 to hit at 500

Can anybody with the Sierra ballistics program, or any program, help me out and tell me how many inches high I need to be at 100 yards to be on at 500?

I have 2 guns I need to know this for:

The first is a 6BRX with the Berger 108 BT (.243) traveling at 3050 FPS.

The second is a .308 with the 168 SMK (.308) traveling at 2,700 FPS.

The following is the same for both: They are both zeroed at 100 yards. The altitude would be 2,000 feet above sea level and temps at 75 degrees.

I can’t find my Sierra program and I need this information by Saturday so I don’t waste a bunch of ammo getting on target. My guess is that I probably need to be about 9 inches high at 100 for the 6BRX, and about 11 for the .308?

Thanks so much to anyone who can help me out.

I use this to get an idea of drop/drift:

http://www.handloads.com/calc/

Here is a free program to calculate what you need. You'll also need the bullet BC to calculate.

http://www.huntingnut.com/index.php?...le=print&sid=3

You are in range with both estimates.

http://www.jbmballistics.com/cgi-bin...j_simp-5.1.cgi

Thank you guys for the great links and your feedback. Looks like I won't need to buy software for that need again.

I use those exact numbers for my BRX and my .308. Our Vel numbers are not that far off.