Early U.S. 25 x 137mm Rounds

[bdgreen]

From a mid 1960's pamphlet on the TRW 6425 Gun system (25mm auto cannon; TRW = TRW Jet & Ord. Division, no longer in business) are these two 25x137mm cartridges listed as AP (APDS or APDS-T?) & HE.

Oerlikon produced or U.S. produced? Or?

Anyone have an example of the AP cartridge?

Info from the pamphlet:

HE projectile = 180 gms
HE weight = 27 gms
Case material = steel
Driving band = steel
Fuze = Super quick, self destruct
Single base propellant = 90 gms
MV = 3610 ft/sec.
Case weight = 227 gms
Tracer time = 3 seconds
HE cartridge weight = 513 gms

AP (APDS or APDS-T?)
Projectile weight = 120 gms
Projectile (tungsten penetrator with alumimum sabot and aluminum ogive material) weight = 80 gms
Propellant weight = 100.5 gms
Steel driving band
MV = 4460 ft/sec.
Tracer time = 1 second
Cartridge weight (with tracer) = 454 gms

 

[hasag]

The amor piercing round of photography seems rather a TPDS, or TPDS-T no?
Saludos

 

[bdgreen]

Hasag,

Good point. The first thing I noticed when I saw the cartridges pictured in the TRW brochure was how different the projectile on the AP round looked.

One point to remember is that the brochure dates to 1965 so the cartridges shown date to at least 1965 if not before.

After some basic research I've learned the ammunition used by TRW was, to no great surprise, produced by Oerlikon.

One correction to the information on the AP round I provided earlier: the entire projectile weighs 120 gm and the tungsten AP core weighs 80 gm.

So to build upon the question presented by hasag; is the cartridge pictured in the TRW brochure an actual AP (APDS) round from 1965 or before or is it something else? Perhaps a TPDS as it existed in 1965 or before?

 

[Tony Williams]

I think it depends on what you mean by "actual" round. AFAIK this cartridge was experimental at this time, so there would have been no service rounds. TRW initially worked on it, but then dropped it. Oerlikon picked up the ball (presumably because they had been working on the ammo, so they decided they might as well carry on) and duly introduced the cartridge in their KBA cannon. I'm not sure when this entered service but it don't think it happened before the 1970s.