Range Report Corrected BC for 6.5 147ELD-M?

[whiskeysierra762]

I cannot get my ballistic computer to match my field data using the factory BC.
I don't have a chronograph and I usually just enter the factory BC and then true the muzzle velocity based off the drop in my Kestrel. Im shooting a 260AI and if I true my drop for 1000yds I get a reverse calculated velocity of 2950fps. However its nothing before or after that range is matching up.
If I change the BC to 0.325 G7 and a muzzle velocity of 3000fps then I can get it to match pretty close.
Is anyone else having to do this and if so what BC are you using?

 

[Reload10]

Not in front of my data, but the factory bc with my velocity had almost perfect elevation at 810yds. Not very far to truly test bc, but it can't be that far off?

 

[whiskeysierra762]

If I plug in the factory BC for my 800yd come up Im 0.3mills high at 500yds and 0.6mils low at 1200

 

[Steel head]

I used to shoot a lot of those through a few barrels.
Generally something in the .320ish G7 was needed if your shooting them from 1200 to 1800.

 

[Reload10]

Here's what I'm using. Only out to 810 though

 

[65x55guy]

Here's what I'm using. Only out to 810 though

Should be noted that Hornady publishes multiple BCs for that bullet based on velocity, which @Reload10 has punched into his app.

I would be more likely to play with a constant MV and use multiple BCs than to try and true a constant BC with a higher or lower velocity.

also, and I’m sure somebody will say this, once you’ve got actual dope then I wouldn’t sweat over the calculator.

 

[Schw15]

I run these bullets around 2810 and i used the drop down bc from hornady i find they work great to 1000 then pretty good to 1400 then past that gotta adjust from what it says dial more. Steel head is right with the .320 past 1400 or so