Trueing muzzle velocity vs BC

seand

WKR
Joined
Sep 22, 2012
Messages
328
Location
Tigard, Oregon
The Revic has Doppler drag model option you can pick instead of G1 or G7. I don’t think it’s the same as AB or 4dof, but it has been accurate for me with Hornady 108’s and 147’s out to 900 with no truing needed, just enter good velocity data from garmin xero.
 

Wrench

WKR
Joined
Aug 23, 2018
Messages
6,242
Location
WA
I typically don't see the bc holding as well once the bullet gets close to the trans zone. Beyond that point twist adjustments can help get closer...but I am still working the kinks out.
 
Joined
Oct 17, 2015
Messages
1,235
Location
British Columbia
Just to make sure I'm barking up the right tree, here's what I did on my new round to true with velocity. This is for field shooting, I don't care much past 1,000 yards.

7 SAUM / 162 ELD-M 46.6gr H4350 22" Barrel / NF NXS 2.5-10

Set my zero, I did a large shot group, moved .25 MOA U and 1.00 MOA R

IMG_7633.JPG

I then shot out to 437 yards and guessed 2850 FPS (no chrono on hand) on my load. AB was telling me my drop from the app with their custom drag model to dial 6.75 for a 31.1" Path

IMG_7634 2.PNG

I shot 3 rounds and found I was 2.04" low

IMG_7611.JPG

I adjusted velocity then to 2781 to achieve 33.1" of drop at 437

IMG_7635.PNG
 

6.5x284

WKR
Joined
May 7, 2015
Messages
1,062
Location
NW MT
If my solver has G7 for the BC, I true velocity in the 500-600 yard range, and BC at the 1000+. If my solver has custom curves, like others have mentioned, I just run with my velocity from Garmin or Magneto and just fine tune from there if needed. My Magneto speed needed a little fps tweak here and there. My Garmin with custom curves has felt like cheating.
 
Joined
Oct 17, 2015
Messages
1,235
Location
British Columbia
Perfect, thank you

I did not take the 7mm 162 ELD-M BC (.670) from the box. I used the CDM on AB then had it return the G1 of .640 to use on my Leica 2800.COM
 
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