Disassembly of a NAPEC (DCP) Model 1381 style 3

[Sanji Himura]

I called Lockmaster's Security Institute since Squelchtone said there was an example of this lock in the Museum there.

I was able to speak to a representative that did tech support for DOD and the Military.

Pretty awesome job from the sound of it. They get calls from the Military over seas that say, "Hey we just took this palace and found this safe and these locks. How do we get into them?"

Any way, they confirmed that this is a very rare lock only supplied the Navy for a short amount of time. The reason for it being dual custody was that it's purpose was to secure containers holding nuclear weapons.

They also said that it is the last, possibly only, dual custody lock issued in the Navy. It sounded like now they are using S&G 951's mostly.

No info on the manufacturer because this was probably bid out on the NAVSEA system and bid on to be made exclusively for the US Navy. So there would be no need to mark anything on it as no one was supposed to ever see it anyway.

They told me this was a very rare lock that should not have made it's way into the public hands and that it should have been destroyed. But they also said there is not really a concern and I don't have to worry about a knock on the door because they are technically retired and none are supposed to be in use now. Whewww..

So, let me throw this question out there, did the expert at all mentioned what is stopping the technology from reaching mass production? I could see ABUS or some of the higher ended lock manufacturers trying to replicate the technology if that wasn't the case.

Why would it even be on anyone's plate for such a lock to reach mass production? Nothing short of nuclear weapons needs two human beings to unlock it at the same time. Bank vaults don't use padlocks, so that's not viable. It was a one off special project. Most commercially made padlocks offer the illusion of security, and the actually well made padlocks just extend the time it takes to get through their shackles, bodies, or lock cylinders.

There has to be a demand for the supply to be introduced, and the price has to be low enough for someone to want to actually spend $200-$1000 on such a padlock. I'm not sure I can think of a current need that fits this.

Squelchtone

Fair enough. I was trying to see some commercially viable option for the lock, but since there was a demand from one entity (The Navy), I can see the reason why the Navy wouldn't want this technology to get out to the public.

On face value, however, for a 27 year old lock, it is still cutting edge, and adaptable. I can't wait to see the goodies that would get stuffed into it.

[phoneman85]

that is one of the coolest, if not THE coolest padlocks I've seen! If it really was for securing nukes, even better! Not to mention the fact there aren't many in existence! You could probably shoot that thing with a 50 caliber, and it would survive. Now I don't know about armor piercing, but you never know.

Would love to find one of these, but from what I've read, good luck.

So, did both keys have to be turned at once, or just both keys used to open it? looks like from the pics, you could use one key, then use the other and it would still open.

[kwoswalt99-]

I don't know about a 50. cal(I assume browning not some of the smaller handgun rounds). In my experience 7.62x54r will penetrate 1" of steel, so I don't know if it would stand a chance against a 50. browning. I'll let cheerIO answer your question.

[GWiens2001]

No, it won't stand up to a .50 caliber rifle round. Never tried using a .50 on one of those NAPEC padlocks, but have used one enough times to say with certainty that there is no lock on board a ship that will stand up to a .50 cal. Sort of like asking if a ping-pong ball can stand up to a 15 pound sledgehammer. Ain't gonna happen.

Gordon

[phoneman85]

Makes sense, and I should have figured that. Even an enviro will get owned by a high power rifle. (there's a vid of that I've seen, think BosnianBill did it).
So, raufoss rounds would be quite effective as well, not that I'd condone shooting a rare lock!

[yono]

HI PAL, Any infos on its top pins? security type or standard? thanks a lot.

[Squelchtone]

HI PAL, Any infos on its top pins? security type or standard? thanks a lot.

Hi yono, nice to see you on the forum. Like most US military padlocks of that time, this padlock used Medeco Classic cylinders in 02 DoD keyway with 6 pin keys. Two of the Medeco Classic key pin heights called for mushroom driver pins, so you would have security top pins depending on the key bitting.

Does that answer your question?
Squelchtone

[yono]

Thanks a lot Squelch.. you are always reliable as ever. regards.

[ARF-GEF]

Wow, what a lock. Drool drool
Now I want one as well

All these military locks, like the SG 951, SG 831 seem to be made from the same rough surfaced grey material. Anyone know what is it?
Never seen this kind of surface anywhere else before.

And apart from the surface for a bunch of obvious reasons any difference between this and average steel we are "used to"?

[MBI]

Wow, what a lock. Drool drool
Now I want one as well

All these military locks, like the SG 951, SG 831 seem to be made from the same rough surfaced grey material. Anyone know what is it?
Never seen this kind of surface anywhere else before.

And apart from the surface for a bunch of obvious reasons any difference between this and average steel we are "used to"?

When I first saw it I thought it looked like parkerizing, like was common on military weapons in the mid 20th century. Parkerizing is a phosphate coating which is still used but is a lot less common these days. Initially it's a similar grey color, with a slightly rough and matte finish, but if the weapons are packed in cosmolene for long term storage, even after being cleaned the parkerizing can take on a slightly greenish hue. I've seen pictures of some older SG padlocks that also looked a bit like they had that slightly greenish/grey tint, which initially seemed to confirm my suspicion but after getting my hands on a few dozen of these locks over the years and seeing the flat grey finish flaking off, I'm reasonably convinced it's just some kind of grey matte paint.

This is not an authoritative answer, just my observations based on about 30-40 S&G and Hi-Shear locks. With any luck someone who actually KNOWS the answer can chime in.

[averagejoe]

Wow, what a lock. Drool drool
Now I want one as well

All these military locks, like the SG 951, SG 831 seem to be made from the same rough surfaced grey material. Anyone know what is it?
Never seen this kind of surface anywhere else before.

And apart from the surface for a bunch of obvious reasons any difference between this and average steel we are "used to"?

When I first saw it I thought it looked like parkerizing, like was common on military weapons in the mid 20th century. Parkerizing is a phosphate coating which is still used but is a lot less common these days. Initially it's a similar grey color, with a slightly rough and matte finish, but if the weapons are packed in cosmolene for long term storage, even after being cleaned the parkerizing can take on a slightly greenish hue. I've seen pictures of some older SG padlocks that also looked a bit like they had that slightly greenish/grey tint, which initially seemed to confirm my suspicion but after getting my hands on a few dozen of these locks over the years and seeing the flat grey finish flaking off, I'm reasonably convinced it's just some kind of grey matte paint.

This is not an authoritative answer, just my observations based on about 30-40 S&G and Hi-Shear locks. With any luck someone who actually KNOWS the answer can chime in.

It is just the finish left after the lock bodies are sand cast. They are made from a proprietary stainless steel alloy which gives it the grey colour. The texture from the sand mold is what gives it the matte finish and it is possible to really polish one up to a high shine. I have had quite a few that ranged from brand new to really beat, some have had patina and other staining but never any that have had a coating that flaked off,

[Phantom1016]

This thread was raised from the dead, indeed.

What's a good source to find interesting locks like these? I peruse ebay and facebook marketplace but are there any brick and mortar stores or swap meets that tend to have good old locks? There are a LOT of antique shops near me (DFW and East Texas) but they rarely have anything interesting for locks and picking.

[Patenter]

Just to add to the ‘historical’ info captured here:

I used this lock daily while in the Navy in the early 1980’s. It was attached to a hasp on a launcher control station aboard a destroyer. To gain access to such a space required that a ‘two-man rule’ be followed, as previously mentioned due to particular weapons capabilities at the time during the cold war. The keys were identified as ‘A’ and ‘B’ keys as marked on the lock.

Two people, one with only ‘A key’ access and the other with only ‘B key’ access would, together, gain access from an armed guard to a large safe with dial combo known to both people. Located within the large safe were two smaller dial combo safes holding the ‘A key’ and the ‘B key’, respectively, each smaller safe having a different combination known only by applicable personnel. Hence, a two-man rule would be established upon access and maintained thereafter. So always at least two people would be present within the controlled space.

I recall that it could be a challenge at times for an ‘A key’ person to locate a ‘B key’ person to perform daily inspections, particularly during rough seas when some folks would become sea sick and unable to assist. The list of cleared personnel was very limited. One time I had to request the ship’s commanding officer to assist me in such mundane chores since all others were incapacitated.

Yes, cool locks that never caused any issues. It was a bit unsettling, however, to have a couple of 19 year olds or the like in charge of such weapons …