20mm Ammunition Can

Something thats been hiding in the attic since my active duty days. It is stamped (raised letter) "20mm AMM BOX MK-3 MOD-3"

It is stincled but some of the letters are worn or blurred. Labeled LITE because it is not a full box.

The lettering reads;
20mm HEI M210 4EA
20MM APT M95 1EA
1305-01-003-2461 A862
HAW 83G001H003
ADL10001-3284937 REV C

I’m curious what you experts know about the rounds and what’s significant about the left hand feed


No expert here, but the ammunition is 20x110mm Hispano-Suiza and as indicated, High Explosive Incediary and Armor Piercing Tracer in a 4:1 ratio. I think this loading was for the M3 lightweight cannon (and perhaps others?) that was used in aircraft. These were percussion primed vs. the electric primed used in the M24 guns which saw most use in B-36 defensive installations. Left vs. right would have to do with which side of the plane the installation was on, be it in the wings or the fuselage. The direction of feed was matched. Don’t know just which planes it was used in, but I would guess they flew off of boats…

Perhaps another poster could show us some nice examples of these…(I assume your box doesn’t still weigh 60 lbs.!)

(edit: Fixed the weight comment.)


Dave was faster…

That would be 20mm Hispano Suiza caliber cannon, M3 and M24A1 in US service.

Packaged, not necessarily produced, at the Naval Ammunition Depot Hawthorne, NV in July 1983.

M36 percussion primer, with 120 grains explosive in the HEI.

Dave, Dave, Dave, Dave, Dave

Boats are what you use to go fishing in. Or what you play with while taking a bath.



There I was trying to be useful for a change and I go and insult every Navy man out there. My apologies are humbly extended.


Tell 'em, Ray! Landlubbers. HA!

I think this loading was for the M3 lightweight cannon (and perhaps others?) that was used in aircraft. These were percussion primed vs. the electric primed used in the M24 guns which saw most use in B-36 defensive installations.

Dave, the cartridges listed on the container are electrically primed and were for the M24 gun. It was used in several aircraft and helicopters (excessively in the Vietnam conflict).

Most interesting, because this is what I recall about the can. It came from a submarine tender in the early 1990s and we only had the older 20mm single guns (I thought Orlikon) that were mounted on stantion mounts, with the shoulder saddles. Guess its safe to say what is written on the can and what was in it was not the same. As QACI I know we (inspectors) went more by the tags on the cans than what was written on them because the tags had condition codes and lot numbers on them. We never associated with carriers or aircraft.

DaveE, don’t let Rick and Ray rag you about using the word ‘boat’. Submarines were referred to as boats and they are plenty dang lethal!

Shotmeister, if I recall right there were deck mounted 20mm M24s which became available after they were not in air service anymore and were later replaced by 25x137 MK38 guns.

Where is Tony Williams? He should enlighten us.


;>) ;>)



Thanks for the kind defense, but at least I got Rick to stop by!


And not to veer far from my very first statement (no expert here), while I did go from memory before, now I’m a bit confused…Went and looked at TM 43-0001-27 and the M95 and M210 are listed as percussion primed. The M97A2 is listed as an electric primed version of of the HEI and I don’t see an electric primed APT loading. The M96 Incendiary is listed as percussion primed. (elsewhere in COTW I see it listed as electric primed!) The percussion primed issues are indicated for the M3 and M24A1 guns. The M97A2 and other electric primed rounds are indicated for the M24A1 only.

I have an inert electric primed M96 of early 1950’s vintage (thus my previous investigations into the subject). Looking at Tony Williams’ fine books Flying Guns and Rapid Fire, it seems the M24 (not “A1”) is electric fired only. The M3 is definitly percussion firing.

So…Perhaps the M24A1 can fire both electric and percussion primed and the designations M95, M96, M210 etc. do not indicate primer type?

I need some learnin’ here!



Rest assured, I am in ambuscade. Ray’s back-up, if you will.

Maybe this is what Shotmeister’s can fed? navweaps.com/Weapons/WNUS_20mm_mk16.htm
If I’m reading this right, there were both electric and percussion primed versions?

Added: If installed on the Mk 68 mount, there would be left and right hand feed options.


With Ray on guard and you backing him up, this landlubber don’t stand a chance!


Dave, it is confusing now. I looked up the “TM 9-1901-1 Ammunition For Aircraft Guns” from 1957 and found the M95 to be electric primed.

The same manual also describes a M95 with percussion primer.

Means there are two cartridges with the same designation but with different primers.

So since it says nothing about “eletric” on the steel container I assume it must have been percussion primed cartridges inside.
Sowith I assume again these cartridges were then not suitable for the M24 (unless it could fire both types).

Thanks, you all is learn’n me!

Dave, the gun we had on my ship was indeed the MK 16 you linked to, including the mount. Looks like they just lifted it off the ship! In my somewhat fogged brain I was imaging a gun we have on the USS YORKTOWN, which is an older model 20mm.

Isn’t it odd how something as simple as an old ammo can that I hardly gave a second thought to could generate so much discussion! Even though Rick and Ray have been uncharacteristically quiet on the subject.(lol)

One thing I DO know about these ammo cans…They are DARN heavy after you have done your stint in the “ammo line”, loading bunches of these (full, of course) aboard ship…SHIP, Dave…SHIP !!!..:) :) :)…



It would seem I’m going to have to make a rather large contribution to the “Retired Sailor’s Beer and Recreation Fund” to get out of this one. All Navy folk can just forward me lists of your prefered brand of beverage and I’ll start working on the “Museum” passes…(smiley thingy here)



For my part, you can just send me the cash. Ray, on the other hand, may prefer a coupon for Metamucil or some such. But you’ll have to talk to him about that. Depends (snerk) on how irregular he feels at the time.


I’m sure you’ve heard the expression “Leave well enough alone”. You should have followed that axiom because now you’ve done offended the entire Naval profession. Except for a few rowdy types like Submariners, sailors are seldom inclined toward “beer and recreation”. Unless, of course, by “recreation” you mean girls, in which case I admit that I may have lusted in my heart on occasion.

I’ll take my contribution in Tums, thank you.