Who wants to play with ballistics that everyone loves talking about?

[MrDeaf]

Part 1.

Okay, so I found a ballistic trajectory program that seems to do the job well enough, but I am having trouble calibrating the missing data, such as cross-sectional area and drag coefficient, to achieve results similar to what is given in navweaps.com.

 

So, what I would like is, with the help of everyone who is interested, to give numbers they think will achieve similar results.

Do note, that, although navweaps is suggesting hard data, there can be some margins of error with shell velocity, etc. because we are dealing with WW2 era naval guns that used gun powder, which never burned at ideal rates.

 

Video of program:

Program itself: https://www.dropbox.com/s/fd1usie6py0qmse/Drag%20Simulator%20for%20Java%201.7.jar

Weapon data: http://www.navweaps.com/Weapons/index_weapons.htm

 

Part 2.

Let's compile this data together and see what sorts of ballistics we are actually dealing with, and not just what we see in the game.

[MrDeaf]

reserved.

[1nv4d3rZ1m]

The data for Cd is in the game files, ask IKU19 he has it all, for the cross section area you can get away with using the diameter of the shell and using it to find the area of a circle. 

[10T0nHammer]

Interesting, when I get to a none work PC, I'll look into this program

[SandraSmiles]

lots of ballistic coefficient programs, but none to my knowledge that will calculate the profile/weight/density of naval projectiles.

If you have the weight in grains, along w/distance, point of impact w/line of sight....you can roughly come to a standard deviation of velocity and  Coriolis Effect

[MrDeaf]

lots of ballistic coefficient programs, but none to my knowledge that will calculate the profile/weight/density of naval projectiles.

If you have the weight in grains, along w/distance, point of impact w/line of sight....you can roughly come to a standard deviation of velocity and  Coriolis Effect

 

That might explain the deviation in range I get with the historical ranges, compared to what this calculator puts out.

[MrDeaf]

IKU19 hasn't gotten back to me, so this is, very roughly, what I have gotten.

I don't have good ranging data for other guns, so they are incomplete.

 

	Muzzle velocity (mps)	Shell Mass (kg)	Darg coefficient approximate	cross-sectional area (m^2)
USN 127mm/38	792	24	0.344	0.013
USN 152mm/47	762	59	0.302	0.018
USN 203mm/55	823	118	0.284	0.032
USN 203mm/55 SHS	762	152	0.315	0.032
IJN 100mm/65	1000	13		0.008
IJN 127mm/50	915	23	0.360	0.013
IJN 155mm/60	920	55.87	0.310	0.019
IJN 203mm/50	840	125.85	0.252	0.032
KM 150mm/60	960	45.5	0.299	0.018
KM 203mm/60	925	122	0.251	0.032
VMF 130mm/50				0.013
VMF 152mm	950	55		0.018
VMF 180mm	920	97.5		0.025
VMF 220mm	985	176		0.038

 

What sorts of graphs would people like?

Normalized for range, or launch angle?

[Raptor_alcor]

IKU19 hasn't gotten back to me, so this is, very roughly, what I have gotten.

I don't have good ranging data for other guns, so they are incomplete.

 

	Muzzle velocity (mps)	Shell Mass (kg)	Darg coefficient approximate	cross-sectional area (m^2)
USN 127mm/38	792	24	0.344	0.013
USN 152mm/47	762	59	0.302	0.018
USN 203mm/55	823	118	0.284	0.032
USN 203mm/55 SHS	762	152	0.315	0.032
IJN 100mm/65	1000	13		0.008
IJN 127mm/50	915	23	0.360	0.013
IJN 155mm/60	920	55.87	0.310	0.019
IJN 203mm/50	840	125.85	0.252	0.032
KM 150mm/60	960	45.5	0.299	0.018
KM 203mm/60	925	122	0.251	0.032
VMF 130mm/50				0.013
VMF 152mm	950	55		0.018
VMF 180mm	920	97.5		0.025
VMF 220mm	985	176		0.038

 

 

What sorts of graphs would people like?

Normalized for range, or launch angle?

 

I'd have to vote range honestly. 

[Cruiser_Haguro]

Anyone still install java in their computer?

[Misniso]

Anyone still install java in their computer?

 

Those that program for Android need it.