Interesting Very Early 90MM APFSDS Projectile


#1

I just traded a new IAA Member for this really cool 90MM APFSDS projectile. I was told that it is probably very early in APFSDS development and a test projectile painted for high speed video studies. It has a very unusual sabot design. Anyone with information or theories, I’d love to learn more about it if possible.

Jason


#2

Congrats…You beat me to a “color tip” !!!


#3

Thanks, Pepper!
I am pretty stoked about this projectile. Hoping someone here may know something about it, especially what case it may have used.

Jason


#4

Fwiw: The painting could indicate the thing was meant to be fired in a rifled gun…? i.e. the sabots were meant to seperate from the arrow by centrifugal forces…?
OR:
The paint was to show any residual rotation if the sabot had slip rings for obturation…?
Just wild guessing tbh.
Soren


#5

Thanks so much, Soren!

That is a great theory and makes a lot of sense. Greatly appreciate your input and thoughts on this.

Jason


#6

Jason,

I do not know much about this subject but here are some reports available on line at Defense Technical Information Center DTIC dtic.mil/dtic/search/tr/tr.html that may or may not be of interest:
90-40mm Saboted APFSDS T320E60 for T208 Gun 1959; Sabot Technology 1973; Recoiless Rifle Technical Information Index 1958-1962; 105mm APDS T382 1959; Fin Stabilised Discarding Sabot Shell Design 1949; Sabot Projectiles for Cannon 1943; Sabot Projectiles Univ. New Mexico 1942 to 1944; Recoilless Rifle Ammo, Firestone Tire Co. 1956; 90mm HEAT T300 1958.

Brian


#7

Thanks big time!

I just spent an hour on that site. Not a lot on this projectile but TONS of interesting document totally up my alley on APFSDS development. Grateful for you sharing this link and site with me.

Jason


#8

So far, my research has found out that this projectile was being developed and studied on a US made 90mm brass case that was modeled after the Russian 115MM tank case. These cases have a very long neck compared to most other tank cases. I’ll look for photos. Nothing like finding the next piece of the puzzle when researching something :-)

J


#9

Here is a photo of my only example of trench art that I ever bought. It happens to be the same Russian 115MM tank case that this 90MM APFSDS projectile was modeled after.

J

Russian 115MM Case

Photo showing the same 90MM APFSDS I have fitted in the US 90MM long neck case modeled after the Russian 115.


#10

[quote=“mausernut”]Fwiw: The painting could indicate the thing was meant to be fired in a rifled gun…? i.e. the sabots were meant to seperate from the arrow by centrifugal forces…?
OR:
The paint was to show any residual rotation if the sabot had slip rings for obturation…?

Soren[/quote]

Soren, maybe not rifled since then the projectile would not need a “reversed cup” sabot design to aid sabot separation by creating the drag required. A “rifled design” would not neccessarily need such a feature (look at the early 105mm APDS of British design).
As you noticed correctly (to my opinion) the special “spiral paint job” is for better observation of possible rotation and evaluation of telemetric data later on.
If Jason is correct with his “extended neck” case design in 90mm and if it was intended to research the Soviet counterpart (and the design principles since it was the first smooth bore tank gun in service) this 90mm might have been a smooth bore too.

Slip rings: The fins on Jason’s 90mm have straight forward edges and are not angled. Many designs using slip rings in rifled guns have angled edges on the fins (the Russians use bending little “tails” on their folding fins on HEAT projectiles for example) to counter the residual rotation.
A fixed obturator ring is very important for smooth bores though. Maybe Jason can tell us what type of ring his projectile has on.

Just my thoughts…


#11

I think you are correct, Alex, about it being a smooth bore gun because the rotating band is ridged and non-slip. I know one design feature of US 105MM APFSDS projectiles made to be fired from the M1 Abrams’ M68 Gun all incorporate a slipable driving band to counteract the M68’s riffled barrel. All of the 120MM APFSDS projectile designed for the M1A1 Abrams tank using the German smooth bore M256 gun utilize non-slipable driving bands.

Jason


#12

Jason, thank you for the info. So your 90mm is a unique smooth bore, nice to see!


#13

Jason, Very nice projectile and great to learn about all your posts!
This 90mm case would be the 90mm T94E5. I’m still looking for a headstamp picture. Possible your projectile is the 90mm APFSDS T371.
Not much of a help but this is the best I can do.


#14

The T208 90/40 mm smooth-bore gun uses the T320 projectile.


#15

WESTERN, I can’t thank you enough! The fact that you ID’d the type classification of both the case and the projectile is incredible! Thanks so much. This is fantastic information.

Jason


#16

Unfortunately, I cannot find more photos or info on this round, but I did learn that it was tested in 1953 as an inert one was sold a few years ago with 1953 on its head-stamp.

Jason