SwiftVets.com

[Wing Wiper]

Chief:

I've been trying to get into the following site to ask some questions/ask for help on this M-79 question. There's a message there saying "Maintenance being performed". I can't get past that, maybe somebody else can give it a try, I'm out of time here. Sorry, buddy.
http://www.vnsfvetakerry.com/

[EODARMY]

Sorry; just started tracking this, so I'm not sure of the issue. I do know M-79's and the ammo fairly well being an old EOD type. A number of He rounds were in use:

M381---2.4--3 meters
M386---14 meters
M397A1--14 meters----air burst
M397--14 meters----air burst
M406--14 meters
M433 HEDP--14 meters---penetrate 2' armor!
M441----2 to 4 meters

I don't now the issue but I don't see the projo being detonated by any amount of rain due to the aluminum ogive. But if this guy fired it into the water/mud (close in) after the projo armed, then that sure as the hell would detonate this round. This warhead is well known for being extremely dangerous after it is armed. You can see that the arming distance for the M381 is only 2.4 to 3 meters---that's a problem for a guy that shoots one into the ground or water! You will note the progression in the series would indicate that the Army felt safety was an issue with the M381's short arming distance. I would think that the M441 may have been for "special issue". Also, the M397A1 and the M397 ---14 meters but with air burst; could also give someone a bad day if they fired it 15 meters into the water or soft mud considering both utilized an ejected frag ball. The frag ball was ejected from the rear approx 5 feet into the air before detonation, thus greatly improving the kill zone! Hope this helps, sorry for not following the whole issue!

[BenDeR]

EODARMY - you should probably have a private converstation with NavyChief.
_________________
USMC res 3rd ANGLICO
1986 - 1988

"Retreat hell! We just got here!"
Capt. Lloyd Williams, USMC

[Wing Wiper]

EODArmy: Could you describe the fuse used on the M386 and M406 rounds? What was the triggering event, a crushing force from the front, or a method which detected the deceleration of the round from striking an object? Thanks.

[Hammer2]

Chief, took me damn near forever but I finally found a website that lists all types of 40mm rounds for M79 & M203. There are technical drawings and data sheets for each one. They begin about 2/3 of the way down the page after the large caliber rounds.

Link here:
http://www.tpub.com/content/explosives/TM-43-0001-28/
_________________
"The price of freedom is eternal vigilence" - Thomas Jefferson
"An armed society is a polite society" - Thomas Jefferson
"The beauty of the Second Amendment is that it won't be needed until someone tries to take it away." -- Thomas Jefferson

[Hammer2]

Most of the fuzes are designated PD (Point Detonating), once armed, they use deceleration to slide a weighted ring forward. The ring pushes on pins that move rocker arms. The rocker arms drive the firing pin into the detonator.
Hmmmm- rapid deceleration, like firing up into heavy rain?
_________________
"The price of freedom is eternal vigilence" - Thomas Jefferson
"An armed society is a polite society" - Thomas Jefferson
"The beauty of the Second Amendment is that it won't be needed until someone tries to take it away." -- Thomas Jefferson

[EODARMY]

What is the question reference the 40MM?

[Me#1You#10]

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