nickwitha_k (he/him)

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Joined 1 year ago
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Cake day: July 16th, 2023

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  • I’ve got a few things that I need to get done in the next few days (hopefully mostly sorted today) but you’ve got me rather intrigued with this as a puzzle. I’ll see if I can get some time to sketch some thoughts out and maybe some high-level implementation of some bits in Python (it’s faster to POC things).

    A few quick thoughts:

    • I think that an existing or novel protocol built on top of the Internet Protocol is likely the way to go. Following the OSI model, you can target Layer 4, with some simple stuff for higher layers. Client/Server (possibly the same binary) and associated automation should handle Layers 1-3 (translating between different carriers for Layers 1 and 2, and handling routing of data packets in Layer 3).

    • Message routing strategies and their impact on OpSec is worth consideration. By this I mean: broadcast-only vs targeted-only vs both vs hybrid. All three have trade-offs.

    Broadcast-only: Makes it harder to know the intended destination of the message. Conversely, by being routed to either all known addresses or all approved addresses, it can be more vulnerable to interception by a compromised endpoint.

    Targeted-only: May be harder to intercept as the path that a packet takes should result in it hitting fewer potential endpoints. Conversely, some form of addressing is necessary to know, at the least, the next hop in transit. This makes tracing the intended endpoint, as well as network hops much easier (ex. running a traceroute).

    Both: Gains the advantages and disadvantages of both approaches, depending on the which mode the data is transmitted in. Ensuring that data is transmitted correctly becomes important and has implications on the requirement of maintaining known good versions of the client/server software to avoid unintentional or malicious improper routing.

    Hybrid: Could take many forms but the one that comes to my mind is a multilevel hub and spoke architecture (I’ll draw this out). Basically, you end up having 2-3 “modes” for a client/server: hub, spoke, and endpoint. One or more client/servers operating in a hub “mode” act like traditional servers, kinda like a bulletin board, holding packets for local delivery or transmission to another hub. Client/servers in the spoke mode act as hops between hubs. Client/servers in the endpoint mode are the actual intended destination (this could be combined with the spoke mode). To protect endpoint identity, the destination could be part of the encrypted data packet allowing an endpoint to attempt to decrypt packets received from a hub locally, making it harder to know which endpoint a message is intended for. This does still require greater visibility of hub addresses for routing.

    • Encryption of packets is vital. Supporting some modularity might be of value so as to allow use of simpler cryptography for PoC but, the protocol should ensure that it is possible to break reverse compatibility (normally NOT what you want to do for networking protocols but avoiding an “it’s an old code but still checks out” situation would be more important).

    • Amateur radio should be avoided both in PoC and hypothetical “production” use cases. The ban on encryption is insurmountable there and illegal use of encryption could lead to hightened visibility because the FCC, historically, does not fuck around with illegal radio signals. This means all wireless should be below 1W in the US, in bands that are legal for unlicensed use.

    • Any physical layer that supports arbitrary data transfers should be possible. The implementation to support it would be part of the client/server. So, Bluetooth, 802.11, LORA, sneakernet, and many others could be hypothetically supported. Again, though, this relies on the protocol’s stack to be and to understand it, either directly, or translated by another component.

    • A web of trust may be a good approach for authentication and identity.







  • You’re very welcome! Also, look at the shape of handguns prior to the advent of self-contained cartridges. They also tend to have a curve to them for the same reasons. You may also see a tendency in modern large-frame revolvers and some 20th century combat revolvers to sometimes have a straighter grip. The goal there being to make re-acquiring the target for a follow-up shot faster. The former use the mass of the gun and sometimes advanced elastomers to soak up some of the recoil, while the later used the mass of the gun and not giving a fuck about the soldier firing it for that purpose.


  • Very good questions. While I’m a pacifist, I know a lot about firearms, how the mechanically with etc (likely an “on the spectrum” thing as a direct sibling has an autism diagnosis).

    One of the important aspects of technique of firing a gun is the hold. Handguns are held differently from rifles and different types of handguns, sometimes even models of the same category, must also be held differently. This is both for marksmanship and for safety. For example, holding a revolver like one holds most pistols puts the support hand in front of the cylinder, which can cause burns or potentially digit amputations (I’ve heard of but have but haven’t read any case studies of the later) due to hot gases and metal escaping from the gap between the cylinder and the barrel or holding many models of pistol too high on the backstrap is likely to cause the slide and/or hammer (if present) to “bite” the hand in the web between the thumb and forefinger. “Hammer bite” is painful but not usually a cause for great concern.

    Bear with me (rawr) for a bit here because this stuff is relevant to your questions. Derringers, however, are notorious for a number of safety-related issues. First, they are small and seem unthreatening to those who are new to firearms. This is bad because they are also cheap and rather more prone to pose accidental dangers than other types of handgun.

    Most basic Derringers are built cheap and simple. This means that, unlike modern revolvers, they rarely have mechanisms like a trigger safeties (mechanism that prevents the trigger from being pulled if a “sub-trigger” isn’t also pulled), safety switch/catch (“normal” safety mechanism found on pistols, rifles, and shotguns that prevents the mechanism from firing until switched to “fire”), or transfer bar safety (a relatively new safety mechanism that reduces the likelihood of a hammer-fired gun going off if dropped). Do note that none of these mechanisms are infallible (see: Tiger King for a disturbing example of a transfer bar failing to function). Additionally, Derringers frequently do not have trigger guards. Their cheap and handy size leads many new owners to put Derringers directly in their pockets, without a pocket holster (a vital piece of safety equipment for ALL pocket carrying). With their lack of safety mechanisms, this has led to numerous and not infrequently fatal unintentional discharges (self-inflicted severing of femoral artery).

    In addition to all of these, Derringers are frequently hard to hold correctly, due to their compact size. My thoughts on possible injuries from the .45-70 Derringer in particular are mainly related to the recoil. Because there is only the mass of the Derringer and curved handle to mitigate the recoil would be one getting full-on punched in the hand.

    The force is exerted along the bore axis (if you do the physics vector chart thingies, the arrows point straight back down the barrel). The handle has a curve to encourage it to roll but that first impulse is likely going to hit on the tiny bit of the arc furthest back before it starts to pivot. Without extra padding in gloves or another way to deflect, dissipate, or distribute that energy, fractures to hand bones are well within the range of possibility. There are further dangers of holding the firearm incorrectly, like getting smacked in the face and/or dropping it, which could lead to accidental discharge.

    Overall, this firearm is a fabulously terrible idea.


  • Really more of anachronistic 19th/20th century century jest. There are two components here. The handgun and the cartridge.

    The your of handgun depicted is called a Derringer, which is typically a small, concealable gun that typically fires 2 shots before requiring reloading. Generally, Derringers fire small calibers because even something like a full 9mm will cause substantial recoil when there is no semi-automatic action or mass to absorb some of it. We’ll come back to the particular Derringer shortly.

    The .45-70 is a copper-cased, centerfire rifle cartridge developed for the US military in the late 19th century. The full classification of the original load being .45-70-405. This meant a .45 caliber (11.4mm) nominal bore diameter, 70 grains (4.54g) of black powder, and a 405 grain (26.25g) projectile. At the time of its adoption, it was recorded as having an effective lethal range of 1,000yds (910m). In 1879, a 500 grain projectile variant was developed with a legal range of 3,500yds (3,200m) - just to repeat this craziness, in 1879, the US military created a blackpowder rifle round capable of causing lethal injuries to those 3.2km away.

    In modern times, the .45-70-405 is considered sufficient to hunt all big game in North America, including grizzlies and polar bears.

    Now, back to that firearm. It appears to be an American Derringer Model M-4 Alaskan Survival. I highly doubt that any of the designers for a moment thought “a .45-70 Derringer is a good idea” and instead likely made it for novelty or to see if it could be done. I found some fun data on the M-4. It has a 4.1" (104mm) barrel length and, firing a 300 grain projectile, exerts 76.18 ft•lbs (103.29 joules) of recoil energy on its user. By compare, a similarly sized Glock 19 9mm firing a 124 grain projectile exerts 5.77 ft•lbs (7.83 joules) and the iconic Magnum Research Desert Eagle in .50AE only exerts 25.46 ft•lbs (34.52 joules) with a 300 grain projectile. So, the risk of injury to the operator is likely rather high and the manufacture and sale is likely rather irresponsible.