I had a dream (literal dream, not "dream" ;)) of a design for a grenade/mine last night.

In it, the ball bearing projectiles had a hole drilled in them as if they were to be used as poisoned shot (as described in my PDF, v1.1) but, instead of posion, they had a small amount of a propellant in the conical part of the hole, with the shot being mounted onto a short stud which contained two embedded wires through which an electrical current would arc to ignite the propellant and launch the projectile sphere.

Whether the propellant was smokeless powder or a primary, I don't remember, but the purpose isn't to throw the projectile at mach 3 at 200 yards, simply to throw it with enough velocity to penetrate into flesh within 10 yards.

Reason for the spigot design is to simplify manufacturing, as I think it simplier to do it this way than to drill a bunch of barrels into a solid block of metal. Also, by making this a propellant driven weapon, rather than explosively projected, you greatly reduce its firing signature, making it less noticable to bystanders as to what is going on, compared to an explosion.

As an area denial weapon, it would be in a cylindrical configuration, with a stake that attaches it to the ground being driven in seperately from the mine, so you're not having to whack it into the ground (BOOM).

When activated, it wouldn't explode all at once as the typical mine does, but rather, fire off one projectile at a time in a random direction, once every second, or more often if desired to present a more intense deterent, or less often to last longer.

Figuring 600 projectiles at 1/second, that's be 10 minutes. 5/second is 2 minutes.

Using multiple devices in an area would present a greater deterent because of the interlocking fields of fire and the random nature of the weapons firing would prevent rushing through.

By making it directional like a claymore, instead of omni-directional, you could block a path quite effectively, making this a PDM.

In all cases, if tampered with, such as being knocked over, the weapon would revert to a "mine" and fire all projectiles instantly.

As a Tri-nade, the weapon would rapidly fire off the projectiles at over 10/second, again in random directions, but with the added effect of those firing against the ground acting to throw the grenade into the air, allowing the others to be fired down above cover, and to cause the tri-nades fragments to richochet all about the room, eliminating dead zones caused by furniture. :p

Diagrams will be forthcoming.

Interesting idea. Though I suspect balls would not be aerodynamically stable enough to do more than spin madly and hit the ground a few feet from launch.
Even a slow spin will totally kill any forward velocity.

Have you tried to drill an accurate hole in a ball bearing? Its a challenge even to get a drill bit to bite.

Tuatara, you could make a mount like this to hold the bearing in place with the shaft allowing the bit nothing to do except drill it, and it would make centering the holes easier.

Ball bearings are awfully hard though, I would worry that it just wouldn't bite without annealing them first, even with the jig you suggest.

Why not use short lenghts of small pipe instead?
Seal one end and fill it with propellant, done.
Would be like a "bottlerocket" (I think that is what You call them...)

How about dome nuts? For those who don't know, they are like normal nuts but with a domed cap on one end, which would slot nicely onto the right size of hollow metal tube filled with the propellant.

Perhaps not as heavy as ball bearings, but bought in packs of something like 50 with no need to drill, they would be easy to do experiments with.

sounds similar to this CIA method of assasination/ area denial, The operative would create many zip guns and camoflouge them to look like sprinkler heads or some other 'harmless' metal device in the area and they were all aimed into the same general spot creating this area of intense fire/ kill zone.
although your design sounds more like a roman candle but instead of stars you have ball-bearing comets. you could easily vary the firing time from full auto, burst fire to semi auto with varying amounts of delay powder in each mine

Another quality idea from NBK!

My take would be to set it up more like the roman candle, combined with a firecracker. Making hundreds of small rockets (effectively what they are) would be very time consuming, and I doubt that you would get a reasonable amount into a BB without losing too much of the mass. It might be better to take hemispheres, and use a gluey explosive mixture to stick them together, then fire those, so that they go up in the air, or along the ground, and then detonate, sending two rounds for the price of one, and ensuring a more reasonable chance of spin not doing funny things, plus you suddenly have an edge and some loudly screaming projectiles.

Try the domed nuts. That way you don't need to drill, and you get twice the projectiles.

A-BOMB, you see things like your drawing in locks, designed to snap drill bits! What happens is the bit slides off, and the cutting edge then either shatters on the BB, or the bit just stalls, or the whole bit snaps due to the sudden shear. It just isn't practical to drill or even cut a properly hardened BB. Even an Alan key is damned hard work, and you can get a flat edge and grip it nicely to drill - I remember destroying three drill bits (2 TiN coated) trying, and only getting 1mm into the 6mm key. Red heat didn't do much to the hardness, either.

Jack's Complete, about annealing, to soften steel, it must be heated red hot and then cooled SLOWLY, cooling it quickly will retemper it just as hard as it was before.

Back on topic...

I know this thread is about simplicity, but if you're going to all the trouble of drilling individual ball bearings or making little rockets from sections of tube the I'll suggest this anyway...

Why not just cut a length of 6mm ID steel tube into 5cm sections, put a single round of .22LR into one end of each, then drill lots of holes in a pipe (drill them the same size as the OD of the steel tube) and glue the loaded tubes into the holes with the primer end on the inside of the pipe, then fill the pipe with KNO3/Sugar or some other incendiary.

As the incendiary burns downwards from the top, the heat generated fires off the primers and spits .22s in all directions. Who cares if the (unsupported at the back) cases rupture or blow open the occasional section of tube? They only have to work once and it doesn't matter what happens to them so long as they spit their 40 grains of lead at a reasonable speed.

The description may be a little hard to follow so I'll try to draw up a diagram.

EDIT: Here's a quick diagram so you get what I'm talking about, in the diagram, the firing tubes don't extend back inside the incendiary tube, which they should to ensure they stay attached.

The diagram also only shows one side of the tube having firing tubes in it, the real one would have them sticking out all over the place.

The fuse can be substituted for whatever ignition method you want.

The spike in the real version would need to be longer so that recoil didn't knock the thing over.

Different incendiaries (different burnrates) may be used to vary the rate of fire.

Fortunately, the whole problem is already solved, about drilling bearings, by using the slingshot ammo sold in Wal-Mart, as it's flat on opposite sides, and isn't hardened at all. :)

You simply set it flat on a drill press table, clamp it with a vise, and drill a hole through the opposite flat-face. :D

A drilling jig would make it simplier than this even, if you could hold a hundred at a time in a plate.

Attached is a diagram of the projectile itself.

Spherical projectiles aren't very aerodynamic, but that's OK because, as stated, it's range is only intended as 10 yards or so. If it goes off at an angle, so what? That's OK too, as it's intended to harrass and delay the enemy, whether through actual casualties, or through simple fear.

If richochets are flying around, bouncing off the ground, at the rate of 10 a second, who'd want to run into that? ;)

This is NOT a roman candle, as that requires length, and the longer it gets, the more bulky it is to carry. The spigot mine can be constructed as a plate with hundreds of studs (spigots) on it, easily only an inch or two in thickness.

By using a motion detector on the claymore trail guard, you'd have it able to delay as long as there's rounds to fire, as it'd only fire when the enemy is exposed, compared to simple timed firing that'd only delay for a couple of minutes at most.

This would be comparable to the sentry-gun setup using the BB machinguns, only much more portable.

Also, because of the compact and simple nature of the weapon, you could make a pocket-sized version, with the plate going over the knuckles and a handle fitting the hand with a firing switch.

Imagine 3 rows, each with 10 spigots, that fire at a rate of 5/second, for as long as the switch is held down. It's lethal range is only a few yards, but it's simple/compact/full-auto/quiet.

Using the 3/8" size shot, you've got a 30-shot .38 caliber solid-state machinegun in your pocket that's not much bigger than a set of brass knuckles, and you can throw it away without leaving a clue, if you use nipolit to cast the handle, as that'd burn very nicely to gas. :D

You can buy tungsten "bullets", which are used as fishing weights, and use them as projectiles instead. Not only are they more aerodynamic, but they're also very dense, giving excellent penetration.

Use of a powerful primary, like the azo-clathrates, would give some velocity, but you'd need to use some sort of buffer inside the projectile to prevent fracturing by the shock.

Or you can integrate the detonator to the nipolit handle, maybe add a bit of shrapnel to it and then you have nearly perfect weapon - when it runs out of ammo, it can be used not as club or bludgeon, but like powerful grenade!
Definitely good idea, NBK!

I'd rather not have anything intended for carrying in my pocket have a detonator built-in, as the results could be painful. :eek:

As it's intended as a firearm, the handle would be combustible, to destroy prints/DNA, that'd otherwise get you busted.

If it was intended as a grenade, then it'd be purpose-built for that, and not as a firearm.

Yes, maybe some heavier blowback can destroy the evidence ultimately - and you with it. For this purpose some really shock resistent BC must be made. Not really a simple job.
However, it would be best if the weapon can burn including the spigots - which isn't probable, because then you must have the spigots out of nipolite... Bad idea, I know. Maybe some easily-burned plastic will do, accompanied with a flash-burning propellant with low burning temperature - so it can not melt too much of the spigot. Or something which burns slowly after ignition, acting like slow fuse for the nipolite. You fire all bullets from spigots, throw the weapon away and after minute or so, the wick-spigots ignite the handle and all is gone

Reason for the spigot design is to simplify manufacturing, as I think it simplier to do it this way than to drill a bunch of barrels into a solid block of metal.

.... you greatly reduce its firing signature, making it less noticable to bystanders as to what is going on, compared to an explosion ...


First, I cant open attachments so I may have the wrong idea ... but,

For what reason would drilling into BB's be easier then drilling into a solid block? At least with a drilled block you have both the containment for propellant and barrel, trying to drill holes in your would-be projectiles and also fitting the "stud" containing electrics to fire them off will be far harder, and not as effective if a short barrel was used. Drilling out a block, easier, better and will let you use it more then once if needed.

This will only ever be a area denial device as you mentioned (or for the dirty word "terrorism" ). If it was chucked into a crowd they would just disperse, effectively you just giving them time to get away, you would be better off with a grenade. 1 shot a second in random directions at low power will not be effective at killing, nor injuring. So reducing the firing signiture goes completely against area denial .. you want the most flash and bang as you can get as thats its only effective use.

Seems like your trying to make things far too complex to ever be effective as an improvised weapon. At least lose the BB's and use small diametre tube as has been mentioned, sit them upright on a hotplate and drop a bit of lead shot in to be cast into the end, easy and aerodynamic.

For a directional charge (1 shot a sec. at 360° wont hold anyone back that matters) a mass of pipes and .22s in the end with a thermal pyrotechnic initiator .. easiest and best. I think xyz has said this, but I cant see his picture.

Simple means reliable! though I personally cant see a realistic situation where it would be useful.

another cheap and easy-to-drill method would be to use fishing sinkers. lead balls have been effectively used in firearms for centuries