Search found 361 matches

by Bill Jurens
Mon Mar 21, 2005 3:20 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Range table

Thanks, Marty1. Your objective is perfectly clear now. Please give me a bit of time to go through my files -- and make a few inquiries -- to see what I can find regarding 15" range tables. I have four or five of these now in my files now, but most, as I recall, were 'corrected' to later dates, and s...
by Bill Jurens
Mon Mar 21, 2005 2:28 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

huh?

I hate to appear to be thick, but I still cannot for the life of me figure out exactly what you are trying to demonstrate by these calculations and graphs, so cannot really respond coherently. If you read back in the thread, you will see that I've really never been able to grasp what you are trying ...
by Bill Jurens
Sun Mar 20, 2005 10:39 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

"Problems" with USN 16" guns, etc.

I am, in conjunction with another author, currently preparing a detailed paper -- an extension of my previous paper on the "Evolution of Battleship Gunnery in the US Navy" -- which will provide comprehensive coverage of the WWII gunnery experiences of the 'fast battleships' and address most of these...
by Bill Jurens
Fri Mar 18, 2005 3:34 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Ballistic coefficients etc. (to Marty1)

Hi Marty: All I can suggest is that you try to numerically integrate a few trajectories and see how they behave. Your observation is correct, of course, certainly in principle, but it appears that the practical effect of the weight change on projectiles this big is much smaller than one might at fir...
by Bill Jurens
Fri Mar 18, 2005 6:04 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Trajectories and velocity drop

I'm not sure exactly what reasons you are referring to, but if you don't believe me, try to run a few trajectories and you will see that if you use the same drag function (i.e. identical projectile geometries) and and compare relatively light high velocity projectiles against relatively heavy low ve...
by Bill Jurens
Fri Mar 18, 2005 2:26 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Velocity drop curves etc.

I ran a few trajectories which showed that the German KDos data vs the British data seemed to be behaving properly. I was going to write a memo explaining this observation, but I see others have 'beat me to it', and the apparent difficulty has been identified, understood, and corrected. The data is,...
by Bill Jurens
Thu Mar 17, 2005 10:53 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Projectile designation

I've read the entire document carefully many times, and so far as I can see, GKdos100 nowhere specifies the exact type of British projectile at all used in their computations at all. How could it? The Germans who wrote GKdos100 did not know the exact weight of the British 15" shell, and were not eve...
by Bill Jurens
Thu Mar 17, 2005 5:14 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

To Marty1 re Drag functions, etc.

I guess part of the problem -- and our confusion -- is that I still don't quite understand exactly what you are trying to do. If you are just trying to do velocity drop vs range for a hypothetical bullet, then -- provided the trajectory remains relatively flat -- even old Siacci methods will do just...
by Bill Jurens
Thu Mar 17, 2005 5:53 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Campbell's data

Marty1 wrote: "Thanks for your thoughts on exterior ballistics for these big shells. I had not come across the variation of form factor relative to launch angle before. I’ll give it a whirl and see if I can creep a bit closer to Campbell’s data. Do you have any opinion on where Campbell derived his ...
by Bill Jurens
Thu Mar 17, 2005 3:50 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Questions from Marty1

Marty1 wrote: "I do have one question for you. You mentioned the velocity data for 15-inch APC MkI is not in doubt. Fair enough. I don’t have firing\range tables for this particular projectile. I only have the J.Campbell Data and the Baden Trials data. As far as recreating this data in the absence o...
by Bill Jurens
Thu Mar 17, 2005 3:16 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Content of GKdos100

My German is admittedly somewhat sketchy, but here is my interpretation of what GKdos100 contains. As noted earlier, the armor penetration information in this document is in the form of a series of six or seven-page pamphlets each of which deals with a particular class of German ship that might be f...
by Bill Jurens
Thu Mar 17, 2005 2:52 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Circulation of Gkdos100

My previous comment that my copy was 'purloined' should not be interpreted by anyone, anywhere as a criticism of Mr. Rudolfsky or Mr. Rico. Both of these individuals no doubt acted in good faith in translating -- or re-translating -- this information and putting it up on the web. Neither has done an...
by Bill Jurens
Wed Mar 16, 2005 5:02 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

GKdos100 ref

Marty1 wrote: "Hi Bill: My Understanding from Jose -- and he can correct if I'm wrong -- is that the two KDOS Figures he posted earlier on this thread were for British 15-inch APC. "38.1cm gun of the British Queen Elizabeth, the 15" Mark I". See the thread on this forum entitled: "Questions About 38...
by Bill Jurens
Wed Mar 16, 2005 3:46 am
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Armor Penetration

Marty wrote: "The question is was an improved windscreed added to to British 15-inch MkI APC after WWI? Or can we take for granted that the Germans KDOS estimate of British 15-inch APC greatly underestimates the projectiles velocity drop vs range?" Please don't misinterpret my comments below as bein...
by Bill Jurens
Tue Mar 15, 2005 6:49 pm
Forum: Naval Weapons
Topic: 1921 firing trials against Baden
Replies: 145
Views: 92133

Armor tests

I may be missing something here, but... The GKdos100 curves etc. represent the penetration of German Projectiles into German armor of roughly WWII vintage, which is -- as one might expect -- all the Germans had to test against. It's not surprising, at least to me, that testing British projectiles ag...