Hornady ELD-X ballistic question

[Citadel99]

From Hornady's website, they list their different perspective on BC for their ELD line of bullets. So here's my question, if I'm using a ballistics calculator like Ballistics AE, do I set up three different "favorites" for the bullet depending on what distance I'm shooting?

• Mach 2.25 (2512 fps* and above) - Velocities above 2,500 fps and distances out to 300 yards.
• Mach 2.0 (2232 fps*) - Use this for mid-range shooting where the bullet spends time in flight after slowing down.
• Mach 1.75 (1953 fps*) - Use this for long-range shooting where much of the bullet flight occurs after velocity loss.

6.5mm 143 gr. ELD-X
MACH 2.25
--0.623 G1
--0.314 G7
MACH 2.0
--0.604 G1
--0.303 G7
MACH 1.75
--0.584 G1
--0.294 G7

 

[Varminterror]

How far are you wanting to shoot? What barrel twist and length?

 

[saiga308]

keep in mind diffrent velocitys may give you diffrent ~ target patterns but with a 6.5 i see little diffrr\ence in the video with powder loads? video time 21:50

 

[Citadel99]

It’s a Ruger Precision Rifle. Most range work in the area will be 100-300. When I can get down to the ranch I can shoot as far as I want and plan to start learning the long distance game when I’m down there.

Mark

 

[Varminterror]

keep in mind diffrent velocitys may give you diffrent ~ target patterns but with a 6.5 i see little diffrr\ence in the video with powder loads? video time 21:50

The dude in the video doesn’t know how to look for nodes - that’s why it all looks the same. There’s plenty of vertical dispersion from group to group in his targets for having been shot at 100yrds. Had he fired his groups at 300yrds and further, the 3 deflections in velocity would have revealed themselves better.

 

[Varminterror]

It’s a Ruger Precision Rifle. Most range work in the area will be 100-300. When I can get down to the ranch I can shoot as far as I want and plan to start learning the long distance game when I’m down there.

Mark

For 0-300, any of the listed BC’s for any velocities will be fine, your MV will dominate the game at that range.

For LEARNING at longer ranges, take the highest BC - which matches your approximate muzzle Mach number - and shoot 100yrd increments as far out as you’re able.

Until you get data from the field out at 10% of your transonic range, you’ll be fine with that one G7 number for that bullet. Which is to say if your MV, optic height, and Density Altitude are good, you’ll be within 0.1-0.2 mils (1-2 clicks) from 0-1300 using a single G7 BC value for the entire range with either AB Mobile or StrelokPro. I don’t use ballistic AE any more, but I expect the same for it. True up your BC once you get some solid in field DOPE at 10% of your transonic.

 

[z7]

As was stated above, pick the The bc that matches your mv for your “try dope”

If should be real close but might not be perfect

When you get the opportunity, shoot at distance and take detailed notes, targets at 300, 600, 900 and 1100 or similar would be great,

Once you are on target and the elevation at that distance is as close to perfect as you can get, compare the real data to your app. If it lines up, you are golden,

If there is a difference of more than .2 mils at any range, tweak the muzzle velocity for 100-600 yds and BC beyond 600 on the app to make the trajectory match your real world experience

This assumes your app has accurate environmental data for temperature and altitude/barometric pressure

Hornady’s 4dof app is free, trasol is a paid app that works really well for me

 

[Llama Bob]

If you use the middle G7 number in a calculator that takes G7 ballistic coefficients, you'll be great.

Many calculators like JBM have built-in velocity vs. BC ranges that may give you a slightly more accurate solution.

 

[Varminterror]

If you’re hitting the published 2700 with a 143 ELD-x, you should be transonic at about 1450-1500, so your truing target DOPE should be shot at 1300. Truing shorter can be just fine, and as I mentioned, you’ll likely be within .1-.2 mils simply by inputting a hand-me-down trued BC, but you’ll likely get your best trajectory by truing at 1300.

 

[mcb]

I believe Ballistics AE is capable of utilizing multiple BC's at different velocities and doing the piece-wise interpolations correctly. I don't have a copy since I am not an Apple guy but a friend of mine was showing me the capability on his copy. I don't know if you can create your own BC/velocity table or if you can only utilize such bullet data that is already entered in the default database from the manufacturers.

ETA: Just talked to that friend that has Ballistics AE and confirmed that you can enter your own bullets into Ballistics AE and create your own table with multiple BC with specified velocity ranges.

 

[Citadel99]

Thanks yall. According to my MagnettoSpeed, I'm getting 2671 FPS on my 143gr ELD-X ammo and 2851 from the Prime 140gr ammo.