greenejc
Well-Known Member
[QUOT"WWP2012, post: 1680764, member: 108485"]I looked thru the Sticky on this and used the working links plus several others to ballistic calculators. I cannot come up with a accurate chart to save my life, they all say I should have way more drop than I actually do. I need some help figuring out why.
Details confirmed at range on paper.
7mm Mag 150g Barnes TTSX Boattail
Barnes Listed BC .450
FPS average 3110 Via Magnetospeed
Wind was from 9 oclock at 10-15 MPH
Temp was 83 degrees
Barometer was 30.19
Humidity was 43%
Shooting angle -10 degrees
Elevation 641'
Scope height to center of bore 1.750
200y zero
300y 2.5 MOA
400y 4.75 MOA
500y 6.75 MOA
I am looking for a app that has the Barnes bullets listed also for a iPhone. I also have tried to create a custom label but their ballistics don't match either, although they are the closest so far.
Thanks for the help.[/QUOTE]
Using the data you gave me and plugging it in to the JBM Ballistics Calculator, I got
1.9 moa for 300 yards, 4.2 moa for 400 yards and 6.8 moa for 500 yards. That looks to be pretty close to what you got at the range. The website is: http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi. I get about the same values using the Shooter's Calculator with 300 yards being 1.90 m.o.a., 400 yards being 4.18 m.o.a, and 500 yards being 6.78 m.o.a. The Shooter's Calculator site is at: http://www.shooterscalculator.com/ballistic-trajectory-chart.php. They're both within about 2.2 inches of your verified impact for each range listed. Both show you at about 5.7 inches low at 300, where you are about 7.5 inches low, a difference of about 1.8 inches, 4.2 moa or 16.8 inches at 400 yards, and 4.75 actual, which is 19.0 inches drop, a difference of 2.2 inches, and 6.8 or 6.78 moa or 33.7 to 34 inches, where you are getting 33.5 inches. You're never going to get a calculator that will be exact. But these are within about 0.6 m.o.a. of your stated results. Hope this helps.
Details confirmed at range on paper.
7mm Mag 150g Barnes TTSX Boattail
Barnes Listed BC .450
FPS average 3110 Via Magnetospeed
Wind was from 9 oclock at 10-15 MPH
Temp was 83 degrees
Barometer was 30.19
Humidity was 43%
Shooting angle -10 degrees
Elevation 641'
Scope height to center of bore 1.750
200y zero
300y 2.5 MOA
400y 4.75 MOA
500y 6.75 MOA
I am looking for a app that has the Barnes bullets listed also for a iPhone. I also have tried to create a custom label but their ballistics don't match either, although they are the closest so far.
Thanks for the help.[/QUOTE]
Using the data you gave me and plugging it in to the JBM Ballistics Calculator, I got
1.9 moa for 300 yards, 4.2 moa for 400 yards and 6.8 moa for 500 yards. That looks to be pretty close to what you got at the range. The website is: http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi. I get about the same values using the Shooter's Calculator with 300 yards being 1.90 m.o.a., 400 yards being 4.18 m.o.a, and 500 yards being 6.78 m.o.a. The Shooter's Calculator site is at: http://www.shooterscalculator.com/ballistic-trajectory-chart.php. They're both within about 2.2 inches of your verified impact for each range listed. Both show you at about 5.7 inches low at 300, where you are about 7.5 inches low, a difference of about 1.8 inches, 4.2 moa or 16.8 inches at 400 yards, and 4.75 actual, which is 19.0 inches drop, a difference of 2.2 inches, and 6.8 or 6.78 moa or 33.7 to 34 inches, where you are getting 33.5 inches. You're never going to get a calculator that will be exact. But these are within about 0.6 m.o.a. of your stated results. Hope this helps.
