Hornady 4DOF - Any Point to Using if Bullet Isn’t in the Library?

[jonesn3]

Hi All,

I’ve been using the Hornady app for a while and gotten pretty comfortable with the general BC Calculator side of the app and have had good results. But I’m interested in using 4DOF, I like the zero angle feature and the fact that they have direct input for elevation and windage offset in units of inches. The BC calculator side of the app has the same thing, but elevation and windage is kinda cumbersome to input correctly (elevation in inches within the the atmospheric zero menu, and windage offset is input either as MOA/MRAD in a different window or the app determine it from the group analysis if you us the “measure impact location” feature).

Anyways, back to the point and the question: is there any point attempting to make 4DOF work with a non-cataloged bullet in the library (ie. user defined bullet parameters)?

I’ve been having technical difficulties with user defined bullets. The 4DOF app bullet selection appears to default to a Hornady, or other bullet defined in the library, instead of using the data that I input for, say, a Barnes 30cal 180gr TTSX BT. I haven’t seen this issue documented online, and the only workaround I can tell is to actually mail Hornady a 50ct pkg of bullets for them to test and add to the collection.

I’ve called customer service and they basically made it sounds like I was having unique app challenges and they didn’t provide any help (pretty frustrating phone call tbh). I did a screen recording, and sent it to the customer support email, but got a “we’ll get back to you” response. I uninstalled and reinstalled, and confirmed the same issue on a buddy’s iPhone Hornady app. The CS rep did mention he was using an Android version of the app, so maybe there’s a software issue with the iOS version…?

There’s a few other “quirks” about the app, like how if you change environmental variables within the HUD page, the elevation adjustment #s glitch to 0.00 MOA, forcing you to exit and re-enter the HUD. There’s more, but not the point for this post.

TL;DR — having issues with inputting and using “user defined” bullet data in 4DOF. Makes me wonder “is it worth it?” Any workarounds?

 

[B Harrison]

I’m having maybe the same problem.
I thought it was me…
and it may be, but yes, and they don’t even have the 180 he SST bullet/ loads on 308/300 WM


Sent from my iPhone using Tapatalk

 

[RME]

As far as I know, 4DOF only works with bullets in the library because those are the only bullets they've done all their tests/measurements on. It doesn't operate on B.C., there's a custom drag model for each bullet in the library. For everything else you have to use the B.C calculator.

 

[jonesn3]

Right, that makes sense and is what I understood about the benefit of 4DOF - the test data behind the bullet library is the secret sauce essentially. I feel like I recall seeing a tutorial showing you can input your own data, I assumed that was still an improvement over the regular BC calculator, just maybe a more generic model. If that’s not the case, I wish they would just remove this button if it doesn’t work within 4DOF. The button appears the same on the BC Calculator side.

 

[nm.otter]

4DOF (the algorithm) depends on full radar-based profiles.

4DOF (the app) includes a BC-based calculator.

Hornady seems to be working through the inclined fire issues.

 

[jonesn3]

Separately, why does Hornady BC Calculator say a reduced elevation adjustment for a right to left wind (90deg) wind?

For an example: 510yds, 3deg angle, 0 wind vs 10mph wind, right to left, the MOA up reduces from about 9 MOA to 8.5 MOA (rounded)? The incline doesn’t appear to the issue. And I can reproduce the same calculated MOA for no wind using the Barnes (TrueData) and Vortex (GeoBallistics) apps, but those apps still give the same elevation correction for both no wind and 10mph. What is the Hornady app doing behind the scenes in this case?

Edit: appears to be the cross-wind jump setting. Found it in the GeoBallistics settings