8.8cm PzGr. 39, 39-1 & 39/43

[Wulfram]

Hello :bigsmile:

I just visited from another forum (wk2ammo), where my callsign is also Wulfram, to ask you guys some questions.

You see I have recently been researching a lot about the 8.8cm guns deployed by the Germans during WW2 and the ammunition they used. However there was one part which confused me, and that was the weight difference between the Pzgr.39-1 & Pzgr.39/43 shells.

It is mentioned in various sources that the only difference between these two shells was the wider driving bands put on the type 43 to be used in the high velocity Pak 43 gun. The weight is often mentioned as the same. But looking at the shells it occured to me that the wider driving bands might have added some weight, only maybe, and perhaps as much as 0.2 kg. And n a couple of other sources I can see that the newer Pzgr.39/43 is actually listed as weighing in at 10.4 kg, which does sounds more reasonable because of the increased mass added by the wider driving bands.

So I was wondering wether there are any collectors here in possession of both a PzGr.39-1 and a PzGr.39/43, and wether I could get one of you guys to actually weigh both the Pzgr.39-1 & Pzgr.39/43 side by side for me to solve this issue. That I would really appreciate

Anyway the conclusion I have come to so far is this:

8.8 cm Pzgr. 39: Driving bands with a outer Diameter of 90.7 mm & width of 12.3 mm. Weight = 10.16 kg
8.8 cm Pzgr. 39-1: Driving bands with a outer diameter of 91.7 mm & width of 12.3 mm. Weight = 10.2 kg
8.8 cm Pzgr. 39/43: Driving bands with a outer diameter of 92.0 mm & width of 17.8 mm. Weight = 10.4 kg

This would explain the many different weights listed out there in various sources. It also seems logical that the weight increased with the increased size of the driving bands.

Anyway I hope to hear from you guys soon

Best regards;
Wulfram :tinysmile_classes_t

 

[Wulfram]

Hmm... guess no'one knows then

 

[jeff w]

Don't exactly have an answer for you but - I recall a US army doc that noted the early AP rounds had a larger burster cavity than the later. The armor penetration of the reduced charge round was slightly better because it had more metal/less cavity. I believe this was also discussed on the Tank-net.org forum. If this sounds like it might be what you are interested in I know they have a good search/archive function - I'm sure the thread would still be there... somewhere!

http://208.84.116.223/forums/index.php?showforum=18

 

[dano1917]

you got the goods

Hey W., I was fiddling on my search engine and got the most amazing hit. I started scribbling down all this info. I was reading, then to my chagrin I read the name of poster, and it was YOU!! Anyway the difference in driving bands should account for the minute difference in weight, may also have other subtle difference. Even if I had the shells, my Wal-Mart bathroom scales (which has 2 indicators, heavy, and not so heavy) I don't have proper equipment to weigh them in. That's one that looks like you already got the goods. I have a dvd blasting right now Which is Steppenwolf live and the song just played was "Shes got the goods" and I was checking your post about the same time. Omen? Karma? Twilight Zone? Dano

 

[HAZORD]

Dano has listed one of the problems with your request. We own heavy things and don't own accurate scales. To complicate the matter, the typical weights listed in books for projectiles include the fuze with tracer and the internal bursting charge. You asked us to weigh our items, and I would assume you know that none of us would have loaded projectiles, but you didn't specify if you wanted them weighed with fuzes installed or not.

The suffix number on German guns typically stands for the year the gun was adopted, so 39 versus 43 would indicate a 4 year difference in age of gun, so lessons learned on the 39 tank gun would be applied to improve the projectile design for the KingTiger 43 gun. Chances are, better steel, slightly different shape, etc. etc. The 43 projo is designed to be driven faster. Faster impact on armor means a more robust structure is required to withstand the impact and penetrate the target, which could dictate a slightly different penetrating cap and larger rotating bands to take the acceleration down the barrel.

In addition to all of this, mass produced items are machined and formed to a manufacturing tolerance that the designers and manufacturing people considered acceptable. That means that every dimension had a maximum and a minimum acceptable size. Cutting tools wear out, making items larger and heavier because the tool didn't remove as much material, etc. So, the heaviest projectile would be one with the main body at the largest diameter and length with the smallest burster cavity, capped with the largest diameter and tallest piercing cap, capped with the longest and thickest windscreen (everything maximum material steel) There would also be a tolerance on the fuze. To further complicate the matter the scales used would not be perfect, so more tolerance is added.

All of these variables in weight caused the projectiles to be divided into weight zones, so that more predictable impacts could be expected. Having us measure our one projectile of each type and considering the result the proper conclusion to your question would be rather reckless.

I would suggest that you question all of your sources for a machining drawing for each projectile 39 and 43. Have someone model these with a good CAD program (Solidworks is excellent), and the computer will give you the weight to whatever number of digits you want. You could also play with the CAD database, altering the dimensions between maximum and minimum and recalculating the weight, and you could get a feel for how things change in weight within a machining tolerance range.

In reality, the person who made the statement that they were the same except for rotating bands, was accurate if you look at them from far enough away. The machining drawings would tell the truth about the answer to your question. That is the rule that they were built to, and Germans are known for their attention to detail.

 

[Wulfram]

Hi guys, sorry for the late reply.

HAZORD, wether the measured weight is with or without the fuze & bursting charge doesn't matter as long as it's noted. My main interest is to find out how much extra weight the wider driving bands added in general.

The same BdZ 5127 fuze and amatol bursting charge was used in all types of the PzGr.39-1 & PzGr.39/43 projectiles. And according to all available documents the dimensions of the rounds were identical, only difference was the driving bands.

So far I've recieved a lot of help from various collectors & historians, but only one was able to weigh his examples of PzGr.39/43's, the results of which are listed below:

1. (reference) 10231 gram Bczw 225
2. 10350 gram Bczw 245
3. 10420 gram hhg A125
4. 10410 gram hhg A151
5. 10340 gram BYE 263
6. 10230 gram Bczw 239
7. 10410 gram ABYE 243
8. 10230 gram Bczw 229
9. 10440 gram hhg A120
10. 10390 gram hhg A152
11. 10260 gram Bczw 252
12. 10430 gram hhg A120
13. 10280 gram Bczw 228
14. 10220 gram Bczw 244
15. 10230 gram hhg A86

First column is the number of shell measured. Second is the weight (10 gram steps) third is the makerscode, sometimes with steel code. last colom is a number, maybe batchnumber. Weights are without fuze & bursting charge. (Many thanks go out to thekees for this valuable information!)

What would be really great and beneficial to my work would be if anyone could weigh their PzGr.39-1 & PzGr.39/43 side by side, using the same scale. Wether the esults are with or without fuze & bursting charge doesn't matter, as I already know the weight of these components.

BdZ 5127: 178 gram
Amatol bursting charge: 59-64 gram

I hope you guys can help me with this