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25x137 HEI-T, MK 210

pzgr40

Well-Known Member
Who can help me on a cutaway drawing of a 25x137 HEI-T, MK 210 projectile (USA). The fuze looks like the fuze normally used on the 20x102 vulcan projectiles.
Regards, DJH
 
The M505 fuze is used on at least 20mm X 102, 25mm HEI for Chain Guns, and 30mm HEI for the GAU-8 cannon on the A-10 aircraft. The photo from ATK, showing all their rounds is correct, but the photo from Global Security shows the wrong round, but the text confirms the use of the M505 fuze


http://www.armyrecognition.com/euro...abilities_at_the_2012_eurosatory_0606125.html

http://www.globalsecurity.org/military/systems/munitions/mk210.htm

http://www.globalsecurity.org/military/systems/munitions/pgu-25.htm

There are versions of the 25mm and 30mm HEI projectiles that take the shorter M505 fuze, and versions that take the longer fuze.

Both of the photos from global security are incorrect for the rounds being discussed in the text. The photos show the longer 25mm fuze.
 

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  • ATK_25mm_ammunition_Eurosatory_2012_international_defence_security_exhibition_Paris_France_001.jpg
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Thanks Haz,
There is another difference in the body of the projectile too. One has a full HE body, with the tracer "hanging" on the base.
The one with the "vulcan fuze I have , has the threaded tracer hole drilled into the base of the body, therefore making the explosives room above it much smaller.
So probably there are more US types of HE projectiles, and I am looking for a cutaway drawing of both.

Thanks in advance,
Regards, DJH

Ps: I found this on the internet:

The PGU-25 HEI is an untraced round that is used on fixed wing aircraft such as the AV-8/B Harrier and AC-130 Gunship. It uses the M505 point detonating fuze

Does this mean the M505 is used only on non tracer rounds?
 
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I believe the M505 is used on all nose-fuzed 20mm HE and HEI rounds for the M50 series ammo and upgrades. It is used on the M246 HEIT-SD round which is carried in aircraft like the F-16 and cobra helicopters. The tracer is internal and low-order detonates the projectile if the M505 fuze fails to contact a target or work in the specified time. So, no it is used on at least one tracer round.
 
This one Mk 210 mod 2 with fuze M 505A3
 

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  • M505A3.jpg
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Hi Hazord and BLU-97, thanks for your awnsers.

To make shure I can explain what I mean, I have pictured both projectiles, as well as an ACAD drawing.
It must be noted that the tracer hole of the short projectile has fine thread.
Thanks in advance.

Regards, DJH
 

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  • 2x25mm dwg.jpg
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When I worked for Primex (the old Olin Defense works) which is now General Dynamics - Ordnance and Tactical systems, we loaded all of these at the Marion, IL plant. Yes the M505 fuze was loaded, but the new PGU chemical reaction fuze used mostly on the new 20mm was starting to be loaded. These were going on the HEI rounds. The 505 has been around for what must be a life time, What isn't shown is the M 919 DU APDS-T. That was such as easy round to load, and no there was never any problem with radiation, the penetrator (body of the arrow) came to us from Aerojet, we screwed don the fins and after that it was a classic load assemble operation.
 
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