Calculations fall apart after 1k yards

[Lesco Brandon]

I’m shooting a few cartridges to 1 mile and I notice that after 1K the calculations are not close to correct. Ive used other apps with the same results but prefer the interface on the Hornady program. When shooting a 110 A-tip @ 3400 FPS the 4DOF was not close to correct despite adjusting the axial form factor maximally. I adjusted the BC on the non 4DOF part of the app and walked it from 200 to 1K and was spot on. Then at 1100 I was off and had to create a different Bullet profile for 1100 by adjusting the BC just for that range. This 1100 BC was off at 1200 so I did the same thing, all the way to 1 mile. Are you finding similar results or do you have to do something similar

 

[Dthomas3523]

Many people use a separate curve for ELR distances and another inside.

 

[Lesco Brandon]

Many people use a separate curve for ELR distances and another inside.

Great. Thank you.

 

[Lowlight]

If you adjust MV at 600, 800 yards, and then do BC at 800 - 1000+ yards the curves are usually better overall.

Your shooting matters too, if you are not grouping well, and not measuring group center from POA, you can have a variation. Also scope testing, the farther you shoot, the more chance of error in the optic appears, as the angle grows.

it becomes a lot more critical to measure out your inputs if you plan to shoot beyond 1000 yards.

 

[Steel head]

On phone apps I’ve had to do multiple BC tables for years.

For some reason my kestrel with AB and DSF is a simple two stage approach that’s was incredibly easy to true up with less hassle.

 

[dragman]

I use old school print outs with JBM ballistics and I have been using the same thing for years and hundreds of guns and it's never failed me. Now I only ever go out too 2000K past that I don't really know.

 

[Fig]

What cartridge are you running to get a 6mm to 3400fps? Is it shooting under a minute @ 100yds?
I'm not criticizing you or saying it isn't safe (your rifle your program), but in my experience trying to wring out that much performance, in terms of velocity, almost always has a steep price in terms of precision. Not that I haven't found a good node above the published maximums, but you must be pretty far out in primer popping country to be getting that kind of velocity even in a WSM or a -284...

Part of your problem may be that high pressure loading doesn't group for shit, and as you float them out there that randomness becomes more and more magnified the further out you get.

Just a thought if you're running so hot...

 

[Lesco Brandon]

What cartridge are you running to get a 6mm to 3400fps? Is it shooting under a minute @ 100yds?
I'm not criticizing you or saying it isn't safe (your rifle your program), but in my experience trying to wring out that much performance, in terms of velocity, almost always has a steep price in terms of precision. Not that I haven't found a good node above the published maximums, but you must be pretty far out in primer popping country to be getting that kind of velocity even in a WSM or a -284...

Part of your problem may be that high pressure loading doesn't group for shit, and as you float them out there that randomness becomes more and more magnified the further out you get.

Just a thought if you're running so hot...

I appreciate your input and the time you took to help me with an issue regarding my DOPE past 1000 yards not being accurate on ballistic applications. My current load is a .243 AI (~58g H20) using peterson SRP brass, 110 A-tips, and 51g of R26 with CCI 450 primers. Bartlien 3R 28" suppressed. I have pushed them over 3500 FPS but my accuracy node is 3395 FPS. I am comfortable shooting this load and it is extremely accurate, 1/2 MOA. I can routinely hit clays @ 1000 yards. These little fuckers smack that steel with such authority it causes boners. I'd like a ballistic application to allow me to plot the curve based on my engagements and extrapolate the data from there VS my current system of having 5 different entries for the same cartridge.