Mk-103 Hartkern question

[pzgr40]

I recently got this -most probably experimental- Mk-103 (I was told) hartkern cartridge. What occurs is that is has a relatively short projectile compared to the “normal” 30mm Hartkern.
As it is Mk-103, the shellcase is electrically primed.
Question: this specific projectile seems to be described in the book “Von Flanschgeschossen und Wolframkernen”. Who has this book and can look up info about this hartkern projectile for me, like year of design, penetration, etc.

Length of the projectile: 77mm
Length of the complete cartridge: 242mm

Regards, DJH

 

[pysall]

My rounds came from Rechlin in the 1990's and came as "dug" with the same MK108 lot numbers along with the Hartkern Ueb. as illustrated.
I have found no reference to the short projectile 3cm Hartkern rounds in Herr Stegmuellers' book...... the only reference being in Herr Petters' book on P579 (45.13) which attribute the projectile to MK 101/103 origins. The illustrated projectiles come in at +/- 74.5mm but do not have the screw-in plug in the base. So, who knows?
Regards

 

[pzgr40/42]

Hey Psyall,
That intrigues me... were the projectiles found along side the 108 cases or actually attached to them?
Were any other ammo remains found in the same hole/dug/site?
There is, at the 'mo, a discussion within a group of ammo collectors in the NL, as to the correct use of the projectile concerned (some of the group specialize in WW2 aircraft ammo). Toughts are divided. Some ... I among them, believe the 108 to not be powerfull enough to warrant a HK proj. for it and think it is 101/103. Having been found on 108... that would solve the question!

 

[pysall]

I was not there when they were pulled out of the ground but I was present at the location where they were being "sorted" for sale. I saw HK, HK Ueb, HK Ueb with vanes and several different variants of the hollow-charge 3cm projectiles. I saw no 101/103 cases - only 108 or a few MK 303. I could only afford the cheaper bits - I believe the rest got sold to collectors in the US for funny-money.
In the workshop where these were being sorted, I saw a lathe and bins containing MK 108 cases and the above-mentioned projectiles. (also 20mm HS404 with German Minengranaten Ueb and hundreds of 13mm TuF with about 12 different projectile types) I could only assume that the items had at one stage been connected together and, coming from Rechlin, I guess anything is possible. Maybe the cases were dug separately to the other bits..... but it did not look like that to me, certainly not in the workshop.
Not solved I'm afraid until we find non-pulled examples.

 

[pzgr40/42]

Alas.. the mystery remains...
Thanks for your answer!
Now... please the adress to the workshop ;-)

 

[panzergranate]

According to 'Vorgänge beim Beschuß von Panzerplatten Bericht 166 Lilienthalgesellschaft' (page 67) different lengths of cores for MK101/103 were testet. The short core has less penetration but works better against sloped armour. They decided to produce the long core as the impact angles in air to ground attacks are not that bad.

google translate: In the course of last winter, the use from attack aircraft in the east against earth targets too of the. on-board weapon destructive effect against heaviest modern tanks like T 34, kW 1 and KW 2 required. For such a commitment only the 3 cm Mk 101 come into consideration. Special bullet had to be developed at an accelerated rate. Only hard core bullets were considered. Decisive for the armor penetration performance was the selection of the suitable hard core. Thick, short cores resulted in average penetration rates for the entire range of the angle of incidence. Slim long cores gave top performance in the area of ​​large impact angles. In the practically possible directions of attack from the aircraft against tanks, the surfaces of the tanks are hit at an angle of impact of 60 to 90 °. the greatest penetration performance was achieved in this angular range achieved with hard core 16 X 85 at 230 g Core weight.

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