Author Topic: Bfx ballistic calculator with 6-dof corrections  (Read 16512 times)

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #15 on: November 30, 2013, 09:12:29 PM »
375CT is there a reason why?

Internet is full of good table-kind ballistic calculators. One of them is jbm ballistics. This one is designed for shooting range use only. On situation where you need to know corrections for one distance. It would make sense to create all new sheet for data tables. It should be pretty easy to do by yourself... Let me know if you need help with it.

Mman, the only reason is to make it more field use friendly, meaning ready to produce tables.

But of course, it's just a request, if you don't find it of your interest, fine by me. Will use it "as is"

Honestly I'm not that skilled when it comes to Excel, and even been trying several times, no way. :(

My world is VB.Net programming.

Unforunately I cannot translate some of the words in finnish (the ones that are white on white)

Again, great work!

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #16 on: November 30, 2013, 09:51:26 PM »

Mman, the only reason is to make it more field use friendly, meaning ready to produce tables.

But of course, it's just a request, if you don't find it of your interest, fine by me. Will use it "as is"

Honestly I'm not that skilled when it comes to Excel, and even been trying several times, no way. :(

My world is VB.Net programming.

Unforunately I cannot translate some of the words in finnish (the ones that are white on white)

Again, great work!

Okay, I'll try to find time for it...

Just for interest what's your application? Are you long range shooter? These 6-dof corrections I have added are not usually very important for short (normal) shooting ranges.

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #17 on: December 01, 2013, 08:16:33 PM »

Okay, I'll try to find time for it...

Just for interest what's your application? Are you long range shooter? These 6-dof corrections I have added are not usually very important for short (normal) shooting ranges.

Mman, thanks for your kind reply. If you just find the time, great!

My main interest is Long Range (up to 2000m), and any tool that helps me to investigate it, the better. I think Robert did a great job by putting together his BfX software.

But like I said, Excel while undoubtedly a good tool for this job, is not where I find myself most comfortable.

How is computed your Vertical Drift? It's as a result of Aerodynamic Jump as detailed by Litz?

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #18 on: December 01, 2013, 09:12:26 PM »
For those ranges it really makes sense to use 6-DOF corrections. If you need to get first round hits lapua's radar data is probably the most accurate way to calculate trajectories. Some Finnish snipers say .338 250 gr. lock base FMJ bullet should stay stable trough transonic velocities. I don't have personal experience however because I don't shoot past supersonic (always less than 1500 m). But if I were to shoot that far I would try that bullet (with 338 LM cartridge ) first because there is radar data available for it as well. You can also download Quick load unlimited for computer and viking ballistics for mobile phone. Both of them include radar data for lapua bullets.

http://www.lapua.com/en/customer-center/lapua-ballistics/lapua-ballistics-software.html

How is computed your Vertical Drift? It's as a result of Aerodynamic Jump as detailed by Litz?
If you mean vertical drift due to crosswind that's a yes. See my first post on this thread.

See also attached excel sheet. Hope that's what you meant.
« Last Edit: December 01, 2013, 09:17:31 PM by mman »

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #19 on: December 01, 2013, 10:29:55 PM »
For those ranges it really makes sense to use 6-DOF corrections. If you need to get first round hits lapua's radar data is probably the most accurate way to calculate trajectories. Some Finnish snipers say .338 250 gr. lock base FMJ bullet should stay stable trough transonic velocities. I don't have personal experience however because I don't shoot past supersonic (always less than 1500 m). But if I were to shoot that far I would try that bullet (with 338 LM cartridge ) first because there is radar data available for it as well. You can also download Quick load unlimited for computer and viking ballistics for mobile phone. Both of them include radar data for lapua bullets.

http://www.lapua.com/en/customer-center/lapua-ballistics/lapua-ballistics-software.html

How is computed your Vertical Drift? It's as a result of Aerodynamic Jump as detailed by Litz?
If you mean vertical drift due to crosswind that's a yes. See my first post on this thread.

See also attached excel sheet. Hope that's what you meant.

Mman, thanks a lot for the new spreadsheet, it's exactl what I was after, now it's a really useful format. ;D

Please, could you explain what is "Effect of atmospheric conditions to vertical zero range" ?

Again, thanks for your time, it's much appreciated.

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #20 on: December 02, 2013, 05:25:45 AM »
No problem. And regarding to your question, please take your time and read this thread through first. Gvp asked this one before.

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #21 on: December 02, 2013, 06:42:14 PM »
No problem. And regarding to your question, please take your time and read this thread through first. Gvp asked this one before.

Thanks.

You wrote :

Coriolis @vertical axis = Eotvos effect = vertical component of Coriolis force ? CONFIRMED

As far as I can tell, it's incorrect to call Coriolis Vertical as Eötvös. They "look" similar, but they are different animals.

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #22 on: December 02, 2013, 07:32:05 PM »
It's says so in Litz's book but there is other errors as well. Now you have opportunity to correct us.

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #23 on: December 02, 2013, 08:29:36 PM »
It's says so in Litz's book but there is other errors as well. Now you have opportunity to correct us.

Well, Litz book is not short on several errors, as you rightly pointed out. :)

And that includes, his poor understanding of Dr. Pejsa's work. I discussed this wih him in the past, and in my opinion, he never understood what Pejsa is all about. He also cites wrongly McCoy on several subjects, for instance on Coriolis.

There are several papers on this subject where this is explained in full detail, and it's clear that some programs like FFS (Lex Talus) also make the same error. Maybe they are looking to impress somebody. But, they are different things, no matter what.

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #24 on: December 02, 2013, 08:43:41 PM »
Still waiting for the education part  :).. I'm eager to learn something new  ;D.

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #25 on: December 02, 2013, 09:37:43 PM »
Still waiting for the education part  :).. I'm eager to learn something new  ;D.

http://www.cleonis.nl/physics/phys256/eotvos.php

just to start, and you can check McCoy on Coriolis too.

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #26 on: December 02, 2013, 09:47:15 PM »
Picture from your link:


For me it still looks like a vertical component of coriolis. What am I missing?

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #27 on: December 02, 2013, 10:04:24 PM »

mman

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #28 on: December 02, 2013, 10:53:35 PM »
Seems like you are right. However I didn't find anything about this from McCoy.

I have to study if it is worth adding this centrifugal effect on my ballistic calculator.

375CT

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Re: Bfx ballistic calculator with 6-dof corrections
« Reply #29 on: December 02, 2013, 11:20:37 PM »
Seems like you are right. However I didn't find anything about this from McCoy.

I have to study if it is worth adding this centrifugal effect on my ballistic calculator.

In my humble opinion, it's not worth the effort, but I have to admit, adding it will make for a more complete solution and I cannot see ill effects at all. So, why not?  :D

You are right, McCoy never mentioned it, I just poined out to him for the reference on Coriolis from a ballistics perspective.

By the way, Coriolis as detailed by Litz is also wrong.