Ballistic calculators that account for the winds effect on elevation adjustments?

[med358-boise]

CDMs are really the way to go for sure

What are CDM packages?

 

[Barbourcreek]

I prefer truing my on BC than using a CDM that is not from my gun

 

[BrentM]

What are CDM packages?

Custom drag models for specific bullets. IMHO it's more for elr or bullets with overinflated bc or where bc can be greatly affected by your rifle set up. It's basically a truing method with the work done for you to a degree.

 

[Barbourcreek]

So what I teach in class
Is get all your inputs correct IE:
scope height
Zero
Twist
Crosswinds
Scope tracking
Velocity from a crono
Environmental
Bullet information

And let your gun provide the BC by truing it
Bottom line the bullet doesn't lie

Thats why EB is designed the way it is

 

[TRG65]

For some of my bullets/loads, I'll never be able to use the CDM. For instance, I point my match loads where I care enough to pay for and use Berger bullets and for those I do a traditional truing. For the Accubond and ELDM/X, the CDM have been spot on for me and much easier.

 

[Barbourcreek]

Back in the day, we had a true velocities I agree the custom drag curve is a good alternate to box BC's, but if you have real velocities, I prefer to do BC
Never been a fan of truing velocities

That's why before my app. Strelock pro was my favorite app

 

[BrentM]

Back in the day, we had a true velocities I agree the custom drag curve is a good alternate to box BC's, but if you have real velocities, I prefer to do BC
Never been a fan of truing velocities

That's why before my app. Strelock pro was my favorite app

Imo truing velocity was do to poor performance of chronographs. Cdm models were far superior to what most people were capable of. Today, we have a host of ultra reliable gizmo's to get most people dialed in beyond their shooter ability. Pretty neat to see the evolution over the last decade.

 

[southpa]

I've been using the revic app. Seems to be pretty good. It goes as far as anyone wants and cost nothing

 

[dfanonymous]

What are CDM packages?

Like has been said, custom drag models.
The thing is, a "drag model" is just that…a model. It's a computer model of a bullet and what it does based off some arbitrary specs.

To that end, it was found later that it didn't fully represent the effects of a modern long range bullet, so thus the G7 was born. This helped predict accuracy out to subsonic.

Drag is complicated and we are over simplifying it here.
The problem is if you shoot a variety of ranges on the fly, you often need multiple profiles for multiple bc for the same gun. Not so much for supersonic, but for out to subsonic. BC is always changing.
That's a reason why you'll hear that people are truing both velocity an BC.

A custom drag model is just a model of THAT bullets flight. One profile. Simple truing procedure.

Frankly it's what wins the competitions too.

 

[med358-boise]

So, for those of us who will probably never have a need or desire to shoot past 800 yards, how many empirical data points do you all typically collect? zero point, max distance and two in between? Since this is essentially, a curve fitting function I would think it would not take more than two interim data points to ensure a high degree of accuracy in the solution?

 

[Barbourcreek]

Actual with mine 1
800 yards is supersonic for most cartridges so that's all I need

I would ensure a perfect zero and true at 800
In your case

 

[dfanonymous]

So, for those of us who will probably never have a need or desire to shoot past 800 yards, how many empirical data points do you all typical collect? zero point, max distance and two in between? Since this is essentially, a curve fitting function I would think it would not take more than two interim data points to ensure a high degree of accuracy in the solution?

Depends what you're trying to do.

If you're trying to just get your dope down; then it's something like James wrote.
I don't do it that order, but generally you have to address each of those things. Regardless if you're hunting, military or doing PRS.

That said, velocity is the biggest factor in super sonic distance. 800 not that far that BC is a huge thing that you need to have down. Where as say 1600y, it needs to be dialed down pretty good.

I wouldn't focus more on wind reading.

 

[BrentM]

Yep, in this case, like most folks NOT shooting elr, just get exact data for the app. That includes tall test the scope. Once that is done and you shoot 800, true the 800. I'll bet you're done at that point and good to go. Wind, positional, and environment, will be your challenges.