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About to test some 30cal loads tomorrow, to dial in a new Scope.
Always had good luck with this free program:
http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi
Just bought a First Focal Plane 4-20X Mildot scope.
personally I'm more familiar with MOA, doesn't really matter, I'm only using the mildots as holdover points.
3.47 MOA = 1 Mil. (can round up to 3.5 moa per mil)
Scope has 4 mildots.
My Standard 30'06 load is: 175grn Sierra matchking .505 BC @ 2950fps. (chrono'd)
Using the JBM program I get a scale out to 600 yards like this:
Little off center, but notice the drop at 600 yards says 10.3 MOA worth.
It's important when you do a calculation off a program like this to "true it" to the real world.
To true this scale you would need to Start with a 200 yard zero'd, rifle. Dial up 10.3 moa, shoot it at a real 600 yards distance and see if the zero from the program matches.
If it doesn't, you need to record the real-world dope, and go play with the inputs on the program till they match the real dope at 600. After that the closer stuff is usually lined up.
Depending on the time of year, sometimes my rifle matches the above scale exactly, other times it's 1/2 moa off. Clearly better than just a guess, though.
Note the Ft/lbs of energy at 600, 1446-lbs. Pretty good smack-down.
Dividing the 10.3MOA by 3.47 (3.47moa= 1mil) gives 2.96 so basically 3 mildots holdover for 600 yards.
Pretty good load, recoil not as bad as a 300 win mag, but certainly more than a 308, (most store bought 308 ammo with a 175grn bullet is like 2700fps.)
Tomorrow I wanna try a lighter alternative load using 150-155grn bullets.
58grns of N160 is what I use to get the 175s at 2950, so with the lighter bullets I'm going with 59grns.
Haven't chrono'd but I did a chart guessing 3090fps as the speed for 150grn Nosler Ballistic tip:
here's another using a 155grn Sierra matchking, (palma)
Interesting enough to get similar drop rates to the 150s, with a Lighter 125grn Bullet you have to push the velocity to 3290fps.
That would take a 300 Win Mag to do that.
With a 125grn bullet at the Speed of 3090fps, (what we chrono'd my then 308 with) It shows:
Not as flat over distance, and with Considerably less Energy delivered.
The 150grn range seems to be good balance of numbers.
Will see how accurate they prove tomorrow.
If you've made it this far, here's a pretty swell stock made in Norway sold by Kelby's for around $690
http://www.grsriflestocks.com/grodas/action-inlets
http://bulletin.accurateshooter.com/2013/01/kelblys-unveils-kts-stock-1-8x24mm-march-and-grs-stocks/
Finally, here's a Ho in a bikini:
Always had good luck with this free program:
http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi
Just bought a First Focal Plane 4-20X Mildot scope.
personally I'm more familiar with MOA, doesn't really matter, I'm only using the mildots as holdover points.
3.47 MOA = 1 Mil. (can round up to 3.5 moa per mil)
Scope has 4 mildots.
My Standard 30'06 load is: 175grn Sierra matchking .505 BC @ 2950fps. (chrono'd)
Using the JBM program I get a scale out to 600 yards like this:
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs) (s) (in) (MOA)
200 -0.0 -0.0 2.4 1.2 2583.9 2.269 2594.0 0.217 38.2 18.3
250 -2.4 -0.9 3.9 1.5 2496.3 2.192 2421.0 0.276 48.6 18.6
300 -6.2 -2.0 5.7 1.8 2410.3 2.116 2257.1 0.338 59.4 18.9
350 -11.6 -3.2 7.9 2.2 2326.0 2.042 2101.9 0.401 70.6 19.2
400 -18.5 -4.4 10.5 2.5 2243.3 1.970 1955.2 0.467 82.1 19.6
450 -27.1 -5.8 13.6 2.9 2162.3 1.899 1816.5 0.535 94.1 20.0
500 -37.6 -7.2 17.0 3.3 2082.9 1.829 1685.6 0.605 106.5 20.3
550 -50.1 -8.7 21.0 3.6 2005.3 1.761 1562.3 0.679 119.5 20.7
600 -64.8 -10.3 25.5 4.1 1929.5 1.694 1446.5 0.755 132.9 21.1
Little off center, but notice the drop at 600 yards says 10.3 MOA worth.
It's important when you do a calculation off a program like this to "true it" to the real world.
To true this scale you would need to Start with a 200 yard zero'd, rifle. Dial up 10.3 moa, shoot it at a real 600 yards distance and see if the zero from the program matches.
If it doesn't, you need to record the real-world dope, and go play with the inputs on the program till they match the real dope at 600. After that the closer stuff is usually lined up.
Depending on the time of year, sometimes my rifle matches the above scale exactly, other times it's 1/2 moa off. Clearly better than just a guess, though.
Note the Ft/lbs of energy at 600, 1446-lbs. Pretty good smack-down.
Dividing the 10.3MOA by 3.47 (3.47moa= 1mil) gives 2.96 so basically 3 mildots holdover for 600 yards.
Pretty good load, recoil not as bad as a 300 win mag, but certainly more than a 308, (most store bought 308 ammo with a 175grn bullet is like 2700fps.)
Tomorrow I wanna try a lighter alternative load using 150-155grn bullets.
58grns of N160 is what I use to get the 175s at 2950, so with the lighter bullets I'm going with 59grns.
Haven't chrono'd but I did a chart guessing 3090fps as the speed for 150grn Nosler Ballistic tip:
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs) (s) (in) (MOA)
200 -0.0 -0.0 2.3 1.1 2707.9 2.378 2441.8 0.207 36.5 17.4
250 -2.2 -0.8 3.7 1.4 2617.3 2.298 2281.1 0.264 46.4 17.7
300 -5.6 -1.8 5.4 1.7 2528.4 2.220 2128.9 0.322 56.7 18.0
350 -10.4 -2.8 7.5 2.1 2441.3 2.144 1984.7 0.383 67.3 18.4
400 -16.6 -4.0 10.0 2.4 2355.9 2.069 1848.3 0.445 78.3 18.7
450 -24.4 -5.2 12.8 2.7 2272.1 1.995 1719.2 0.510 89.7 19.0
500 -33.9 -6.5 16.1 3.1 2190.0 1.923 1597.2 0.577 101.6 19.4
550 -45.2 -7.8 19.9 3.5 2109.6 1.852 1482.0 0.647 113.9 19.8
600 -58.4 -9.3 24.1 3.8 2030.9 1.783 1373.6 0.719 126.6 20.2
here's another using a 155grn Sierra matchking, (palma)
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs) (s) (in) (MOA)
200 -0.0 -0.0 2.3 1.1 2715.9 2.385 2538.2 0.207 36.5 17.4
250 -2.1 -0.8 3.6 1.4 2621.8 2.302 2365.4 0.263 46.4 17.7
300 -5.5 -1.8 5.3 1.7 2528.6 2.220 2200.2 0.322 56.6 18.0
350 -10.3 -2.8 7.4 2.0 2437.2 2.140 2044.1 0.382 67.2 18.3
400 -16.5 -3.9 9.9 2.4 2347.8 2.062 1896.7 0.445 78.3 18.7
450 -24.3 -5.2 12.8 2.7 2260.1 1.985 1757.8 0.510 89.7 19.0
500 -33.9 -6.5 16.2 3.1 2174.3 1.909 1626.8 0.578 101.6 19.4
550 -45.2 -7.8 20.1 3.5 2090.3 1.835 1503.6 0.648 114.0 19.8
600 -58.5 -9.3 24.4 3.9 2008.3 1.763 1387.9 0.721 126.9 20.2
Interesting enough to get similar drop rates to the 150s, with a Lighter 125grn Bullet you have to push the velocity to 3290fps.
200 -0.0 -0.0 3.0 1.4 2760.4 2.424 2114.5 0.199 35.1 16.7
250 -2.0 -0.8 4.7 1.8 2637.3 2.316 1930.2 0.255 44.8 17.1
300 -5.2 -1.7 6.9 2.2 2517.5 2.211 1758.8 0.313 55.1 17.5
350 -9.9 -2.7 9.7 2.6 2400.8 2.108 1599.6 0.374 65.8 18.0
400 -16.0 -3.8 12.9 3.1 2287.2 2.008 1451.8 0.438 77.1 18.4
450 -23.8 -5.0 16.7 3.5 2176.6 1.911 1314.7 0.505 88.9 18.9
500 -33.4 -6.4 21.1 4.0 2069.1 1.817 1188.0 0.576 101.4 19.4
550 -45.0 -7.8 26.2 4.5 1964.8 1.725 1071.3 0.650 114.5 19.9
600 -59.0 -9.4 32.0 5.1 1863.8 1.637 964.0 0.729 128.3 20.4
That would take a 300 Win Mag to do that.
With a 125grn bullet at the Speed of 3090fps, (what we chrono'd my then 308 with) It shows:
200 -0.0 -0.0 3.2 1.5 2582.6 2.268 1850.9 0.212 37.4 17.9
250 -2.4 -0.9 5.1 2.0 2464.2 2.164 1685.1 0.272 47.9 18.3
300 -6.2 -2.0 7.6 2.4 2348.9 2.063 1531.1 0.334 58.8 18.7
350 -11.5 -3.1 10.5 2.9 2236.7 1.964 1388.3 0.400 70.4 19.2
400 -18.6 -4.4 14.1 3.4 2127.4 1.868 1256.0 0.468 82.5 19.7
450 -27.7 -5.9 18.3 3.9 2021.3 1.775 1133.9 0.541 95.2 20.2
500 -38.8 -7.4 23.2 4.4 1918.5 1.685 1021.5 0.617 108.6 20.7
550 -52.3 -9.1 28.7 5.0 1819.2 1.597 918.4 0.697 122.7 21.3
600 -68.5 -10.9 35.1 5.6 1723.7 1.514 824.5 0.782 137.6 21.9
Not as flat over distance, and with Considerably less Energy delivered.
The 150grn range seems to be good balance of numbers.
Will see how accurate they prove tomorrow.
If you've made it this far, here's a pretty swell stock made in Norway sold by Kelby's for around $690
http://www.grsriflestocks.com/grodas/action-inlets
http://bulletin.accurateshooter.com/2013/01/kelblys-unveils-kts-stock-1-8x24mm-march-and-grs-stocks/

Finally, here's a Ho in a bikini:

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