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Posted: 12/12/2001 2:45:36 PM EDT
How stable/unstable are 20mm HEI projectiles? I come across them from time to time out in the desert. I’ve found lots of old 20mm casings, some with headstamps from as far back as the 1950’s. I assume that the projectiles are just as old.

Most of the projectiles I’ve run across are discolored, but I’ve seen a few that are clearly yellow with “HEI” marked on them. Common sense tells me they are dangerous, but how dangerous? [xx(] Thanks.

Mike
Link Posted: 12/12/2001 2:59:54 PM EDT
[#1]
I don't recall any dates, but older HEI projectiles do not have the safety features of newer stuff.  1950 vintage is definitly of the "old breed."  I wouldn't touch it.  Newer stuff has an out-of-line firing pin (to state it simply) that requires so many rotations when fired to arm.   Was downloading an AC-130 when someone managed to pinch the tip of a round causing the primer to detonate.  Gave everyone a jump, but nothing more, thankfully.  If you find any projectile sans casing, consider it armed.  If you look at the rotating bands (bearing surface) you may be able to see rifling marks indicating it was fired.  As I recall, HEI fired from the AC-130A's and H's detonated less than 50 percent of the time.  Be safe.

Eddie
Link Posted: 12/12/2001 3:12:14 PM EDT
[#2]
You might be able to pick up a thousand of them without anything happening.  You could however, have the next one detonate on you.  Don't mess with them.  If I were called out, I would detonate them right where they lay.

EOD stands for Explosive Ordnance Disposal.
Link Posted: 12/12/2001 3:14:38 PM EDT
[#3]
Yes...all the projectiles I've seen had the rifling marks on the bases and thusly had been fired. Many had the tips bent from impact into rocks/dirt.

By the way, EOD guy, this crap is all over the place near the Chocolate Mountains Gunnery Range. Nowadays, the Navy does their straffing far behind the mountains, but I guess back in the old days it was a free-for-all.
Link Posted: 12/12/2001 4:54:17 PM EDT
[#4]


EODGuy these look farmiliar?

[img]wsphotofews.excite.com/029/Ye/rB/Vb/kr49306.jpg[/img]


[img]wsphotofews.excite.com/031/Z4/kH/s9/kK37624.jpg[/img]



Link Posted: 12/12/2001 4:58:26 PM EDT
[#5]
I wish I could find some of these things laying out in the middle of nowhere.

Can you say [shotgun] [red]TARGETS![/red][50]
Link Posted: 12/12/2001 5:13:05 PM EDT
[#6]
BAd Ponyboy bad.

You sound like those guys in Kansas City about 10 years ago that took turns shooting into an explosive magazine in a rock quary. I think one of them lived.
Link Posted: 12/12/2001 5:17:08 PM EDT
[#7]
I grew up near a Navy Base in the desert.  This kind of stuff turns up, ocasionally.It was considered an extremely bad idea to mess with any of it.

When you play around with old, rusty bombs, sooner or later, you'll be blown up.  So, don't do it.

I remember looking at an old National Geographic in which the author (reporter?) went to France to write about all the tons of rusty, leftover munitions from WWI.  Yes, WWI.  Farmers are periodically blown up as they plow their fields, cause they hit some old "dud" round.  It is so commonplace, that the farmers just stack up the old rusty artillery rounds on the edge of their fields, and Bomb Disposal trucks it away.  All this is done with absolutely NO Fanfare, to keep tourists ignorant and happy.  Rusty 75mm "French" ammo looks like old rusted cans of hairspray.

They take the poison gas shells out to the coast and burn the stuff up, evironmentalists be damned.

---------
"You'll be sssooooooorrrrrrrrrryyyyyyyyyy!"
Link Posted: 12/12/2001 5:17:25 PM EDT
[#8]
Hey Saltcreek,
How is the old 2507N&S?
Many is the time I spent out there with the DASC as on-site range control.
The cool thing was that for WTIs the officers all had to go in to Yuma for "Debrief" (get face time and go drinking with the students to help out come promo time) and so they had to leave at 4 to get there, which meant yours truly and his cohorts would be running the arty and air out there all night from 1600 to 0800 with ourselves to supervise us.
Then there were the SEAL pricks, and all their priority needs that you had to do for them right now...oh, and they would speed through our camp day or night like jackasses, and would never never stop the white SUVs to give a guy walking a ride, in town or in the desert...but we had to re-do the whole schedule for their BS (right ;-).
And Niland.....7 churches...2 bars...one hill covered with colored rocks that say dumb things...and a bunch of people selling stolen stuff to each other at that RV camp on the old base pads by spihon 8.
I spent way too much time there.
Link Posted: 12/12/2001 6:08:29 PM EDT
[#9]
Good advice from all. Heed it.  The newer Air Force M56 series 20MM (M505 fuze?) fuzes are spin armed and don't arm till they have traveled a certain distance from the barrel.  The older (M51?) fuzes were held by nothing more than friction and shear pins and were consider dangerous, hence the upgrade to the M505.  

I don't know squat about what kind of fuzes the Navy uses though.  

I supervised an inspection operation at Gila Bend in 1980 that involved 20MM brass and live rounds picked up on the range; 22 BDU-33 crates worth.  

We found some very cool stuff in those crates including some of the older M118 practice bombs from the 1930's.  

The only scare I had was when I came back from a break to find one of my Airman "opening" the rounds by separating the projectiles from the cases, pouring the powder out on the ground and lighting it with his lighter.  He was supposedly the son of a mob oriented NYC construction magnate and eventually was told by the Air Force that they no longer required his services.  Between him and another Airman I had who I'll refer to as "hippie/conspiracy wench"......I had a pretty entertaining TDY at the good old "Space Age" hotel in beautiful downtown Gila Bend, AZ.

IYAAYAS
Link Posted: 12/12/2001 6:39:03 PM EDT
[#10]
Link Posted: 12/12/2001 6:57:24 PM EDT
[#11]
On a practice shoot once, we occasionally had a 5" round detonate as soon as it armed, so I'd be reluctant to even touch anything I found on the ground.

Does the 20mm brass whistle when it falls?
Link Posted: 12/12/2001 9:40:14 PM EDT
[#12]
Mate, anything HE, dont't fuck with it. PERIOD. Just leave it where it lies, and move along.

The last thing you would want would be to have it at home, and after falling or being dropped, going off, killing you or a family member or a friend. If its been fired, it may be armed depending on what it is.

As I said, just leave it alone. take a pic if you wanna.
Cheers, and beers
1feral1
Sydney
Link Posted: 12/12/2001 9:50:43 PM EDT
[#13]
As a side note, I imagine possession of such items would be considered possession of an unregistered destructive device.

Primary concern should be not blowing yourself up, but of secondary concern would be not having BATF blow you up.
Link Posted: 12/13/2001 5:37:38 AM EDT
[#14]
JIMBEAM,

It's amazing how they all landed so close together, and in such neat rows too.
Link Posted: 12/13/2001 6:46:45 AM EDT
[#15]
Hey Happyshooter -

2507N doesn't seem to show much activity these days. A few years back it was pretty active; I don't know why it's so quiet now. I used to hear full auto small arms out there in the SWAT area and see a gunship or two doing some minigun practice. These days I just see some F-18s or Harriers cruising by.
I don't know about 2507S as I never go down that far South. On a side note, I once found two spent LAW tubes on the fringe of the range (I wouldn’t dream of going ON to the range!). This was in ‘97. Who uses LAWs in the Navy? Maybe they were left over from some survivalist who owned them illegally.
Anyway, the CM gunnery range aint what it used to be. Maybe they’re not going to use it anymore.
Link Posted: 12/13/2001 10:39:26 AM EDT
[#16]
TRW.....AMMO SUCKS!!!!!!IYAAYAS......IF YOU AIN'T AMMO YOUR WAITING ON THEM.               B.B. STACKER. LOL...J/K .  WHERE ARE YOU DOING YOUR TIME?  
Link Posted: 12/13/2001 3:11:00 PM EDT
[#17]
If what they told me during a safety brief is corrected LAWs have some very sensitive piezoelectric crystal in the fuse.  The temperature difference caused by your shadow could cause it to function. At least that was what our EOD/UXO Techs told us.  
Link Posted: 12/14/2001 5:54:33 PM EDT
[#18]
Quoted:
TRW.....AMMO SUCKS!!!!!!IYAAYAS......IF YOU AIN'T AMMO YOUR WAITING ON THEM.               B.B. STACKER. LOL...J/K .  WHERE ARE YOU DOING YOUR TIME?  
View Quote


Retired in 98.  Now a civilian at Hill AFB here in Utah.  

Sheared any umbilicals on your caps lately?  

Did you finally ever learn how to fill out a 2434...LOL! (1,2,6,7...)  

You damn weapons troops gave me an ulcer!  Nice to be able to harrass one again...LOL.  Nice talkin to ya...Keep your powder dry!
Link Posted: 12/14/2001 6:45:13 PM EDT
[#19]
Link Posted: 12/14/2001 7:04:49 PM EDT
[#20]
Quoted:
.  The newer Air Force M56 series 20MM (M505 fuze?) fuzes are spin armed and don't arm till they have traveled a certain distance

IYAAYAS
View Quote



Loaded the M61A1 for four years on the F-15E and NEVER saw a spin fuze on a 20mm round.  I don't know how you'd get it to go down the barrel.  I think the spin fuze you're talking about is the M904, M905 used on bombs.  and Jim462 is right....

if you ain't ammo, you're waiting on them!!!!!
Link Posted: 12/14/2001 8:03:33 PM EDT
[#21]
Doorgunner not sure about 20mm but from what I have seen on larger rounds the round has to spin above a certain rpm for a specific amount of time before the forces extended on the round from this spinning cause pins to move and/or fuse components to line-up properly.  It's not a fan type fuse everything is internal.
Link Posted: 12/15/2001 5:33:44 AM EDT
[#22]
doorgunner84,

What JIMBEAM is referring to as "spin armed" might more accurately be referred to as centrifical arming where the centrifical force in the spin of the projectile allows an out of line detonator to move into place in line with the firing pin.  What you are referring to is an arming vane on the fuze which spins in the air stream after release of the bomb.  The spinning vane moves a shaft that is blocking the out of line detonator, allowing the detonator to move into place.
Link Posted: 12/15/2001 5:41:56 AM EDT
[#23]
Still dealing with my sadness that 2507 is not being used anymore......
Somebody tell me if on the Az side Stoval (the railroad box with a name on it north of the old airstrip halfway between yuma and gila bend) is still being used?
Link Posted: 12/15/2001 1:34:18 PM EDT
[#24]
EOD_GUY,

Must have just misunderstood what he was talking about....  thanks
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