long range ammo MiniBoy Mark I

[Moonbogg]

This is a real trick isn't it. To come up with something that doesn't hurt performance and that will actually do its job is not easy. it sounds ridiculous, but what about a decent pile of light weight fishing line with a bright colored streamer tied to the end. Tie it to the round and let the line coil up on the floor with the streamer tied to the end of the line.
It would just have to be long enough so that when miniboy buries itself 10 inches into the dirt, the streamer will still be visible above ground and you might catch a glimpse of its trajectory while in flight to predict the general area where it landed.
I suggest several bystanders at various distances down range, with the idea each one might catch a glimpse of the thing. If there are cliffs around, that is great. Get some people with video cameras up high enough for a semi bird's eye view of the whole operation. Chances are they will see more than you can from directly behind the thing. Have them view the trajectory from the side at something like 200 meters, 500 meters and 700 meters, or divide the trajectory however you see fit for its predicted length of travel.
Despite being a nice round, it may tumble and not go nearly as far as anticipated. That is the simplest and most realistic ideas to implement that I have so far come up with.

EDIT: Maybe simply stuff some flower in a hole with the hopes that upon impact it makes a white splash zone. Also, whatever method you try, test it out with something else first. For instance, the fishing line might break or burn apart upon ignition.

EDIT AGAIN! You could easily bundle up the line and the streamer inside the sabot, protecting it from some of the violence of ignition and barrel friction. It should unravel after the sabot separates.

[MrCrowley]

You mean the fishing line and streamer would fly behind the projectile? Assuming the projectile does fly correctly, the drag would probably limit range to ~800m or less

No cliffs by the beach either, the highest elevation is about 20'. I wouldn't want to put people further out than a few hundred meters either, like you said there is a risk the projectile doesn't fly very well.

The talc powder/flower idea JSR, you and a few others have mentioned does seem tempting but I'm beginning to think it'd be quite hopeless. The powder would need to be hard like salt or pepper grains as flower and talc might compact and stick together. The holes coming out of the MiniBoy are also quite small and I doubt much powder would even fall out at its firing angle.

An idea that could work for others designing long range projectiles in the future is some form of pressurized projectile that fires out a dye, coloured powder or confetti/streamer upon impact. I had some ideas in my head to convert MiniBoy that way but nothing sensible and convincing enough that could be added easily with little modification.

For future projects, people should try find a target to hit from a calculated distance whether it is an empty barn or hard sandstone cliff face (soft projectile nose with dye inside?). With a calculator, optimal winds and projectile, a barn wouldn't be too difficult to hit from several km I don't think.

The cake mix is ordered and should come by early next week and testing will commence soon after. If things look promising, it will most likely be the method I go with.


Edit: Just to reiterate:

Will the cake damage the projectile any more than just superficially?
Can the cake be crushed up in to a powder when it has dried and be eaten that way?

I'm worried the heat might damage the projectile severely. As for crushing the cake mixture, I could set it inside the projectile but I'd rather have it in powder form.

[jackssmirkingrevenge]

For future projects, people should try find a target to hit from a calculated distance whether it is an empty barn or hard sandstone cliff face (soft projectile nose with dye inside?). With a calculator, optimal winds and projectile, a barn wouldn't be too difficult to hit from several km I don't think.

A tank can be hit from that distance, but by a projectile travelling at mach 5+ and even at that distance trajectory isn't exactly a straight line - hitting it with a barn with a mach 1 projectile is a bit of an impossible task without finely calibrated sights and accurate weather data.

Got me self some digital scales 1000g x 0.1g for $7. Got the weight correct of all my coins. I am impress.

Bought me 0.01g scales off eBay for a similar silly price, checked it against the 0.00001g balances at work and it matched up fine.

The cake mix is ordered and should come by early next week and testing will commence soon after. If things look promising, it will most likely be the method I go with.

Suggestion - can you stuff one of these in the miniboy?

If so, I would hook that up to some steel wool and a level switch that would activate after the projectile reaches apogee, you'd get a mid-air burst of smoke and no problems with a smoking projectile in the barrel.

[MrCrowley]

Suggestion - can you stuff one of these in the miniboy?

If so, I would hook that up to some steel wool and a level switch that would activate after the projectile reaches apogee, you'd get a mid-air burst of smoke and no problems with a smoking projectile in the barrel.

Just calipered MiniBoy at 12.6mm inside diameter at its widest point, so no, unfortunately. Can a level switch fit inside the MiniBoy do you think?
I like your thinking though, very cool.

On another note, been doing some more looking around at FM transmitters because I can't remember if I threw the idea out because of the antenna or transmission distance. A transmission distance of 100m is acceptable at this stage, previously I may have dismissed it for such performance. My last 'push' for the FM transmitter will be posting a message on an appropriate forum and seeing what they think.

[jackssmirkingrevenge]

Just calipered MiniBoy at 12.6mm inside diameter at its widest point, so no, unfortunately.

Lots of button cells in series?

Can a level switch fit inside the MiniBoy do you think?

What the heck, make your own - some mercury from a thermometer (but really a sliding bit of metal like a small BB will do), a plastic tube and some epoxy and you're sorted.

I had suggested something similar a while ago for parachute deployment:

On another note, been doing some more looking around at FM transmitters because I can't remember if I threw the idea out because of the antenna or transmission distance. A transmission distance of 100m is acceptable at this stage, previously I may have dismissed it for such performance. My last 'push' for the FM transmitter will be posting a message on an appropriate forum and seeing what they think.

The issue at this point is fitting it inside the Miniboy - again, this shouldn't have been an afterthought, but LeMaudit and his francophone machine-first-ask-questions-later attitude made it otherwise

[MrCrowley]

What the heck, make your own - some mercury from a thermometer (but really a sliding bit of metal like a small BB will do), a plastic tube and some epoxy and you're sorted.

Ahh I see what you mean. Realistically, how reliable can a homemade one be? I assume I'll have to be freakin' careful not to tip it forward once armed

Based on what you've said and a quick 5 minute read, the BB will be at the 'back' end of the tube where it will stay until the projectile starts to lose the war against gravity and changes orientation forcing the BB to roll forward and complete a circuit, igniting the cake mix?

Edit: With a BB, I'll need to make sure it doesn't bounce or anything, perhaps a long tube can fix that.

[jackssmirkingrevenge]

Ahh I see what you mean. Realistically, how reliable can a homemade one be?

As long as it's strong enough not to deform or jam due to the firing shock, it should work extremely reliably. Heck, if it jams, the impact with the ground will unlock it

I assume I'll have to be freakin' careful not to tip it forward once armed

I would be fuçking careful, just to be safe.

I love my Spanish keyboard

Based on what you've said and a quick 5 minute read, the BB will be at the 'back' end of the tube where it will stay until the projectile starts to lose the war against gravity and changes orientation forcing the BB to roll forward and complete a circuit, igniting the cake mix?

Yes, pretty much. Added a diagram to the previous post.

Don't research them too much, this is the sort of thing the bad guys use as anti-handling triggers on their "devices" and you wouldn't want to end up on another watch list

[MrCrowley]

Don't research them too much, this is the sort of thing the bad guys use as anti-handling triggers on their "devices" and you wouldn't want to end up on another watch list

...and I just bought some KNO3

Thanks for the idea by the way, tomorrows uni lectures won't be wasted writing down notes

[jackssmirkingrevenge]

...and I just bought some KNO₃

tomorrows uni lectures won't be wasted writing down notes

If you had to see my university notes... I was the peak of my nihilistic "Nothing matters, we're essentially all highly evolved monkeys clinging to a rock that's falling through space and the rock itself is dying." phase - haven't quite grown out of it completely but I'm a happier person now

[al-xg]

You can get tiny level switches, and they're cheap.


You could always cut up a 9V battery and use the mini cells inside (after checking which brands use the cylindrical ones of course ), or even use a charged capacitor, it only has to work once.

A press to break micro-switch could prevent any triggering whilst in the barrel.

fuçking

Pretty hard to pronounce in most cases, in French, "Fussskingeurrr" ?

[saefroch]

Nope, if you take the sugar off the heat, it'll just re-solidify and you'll be pouring the other ingredients onto a caramel slab. You need to keep it on the heat, but not so hot that it begins to darken, because then you could literally be in danger of burning the cake already. It's possible with really good heat control to melt the sugar into a clear liquid, I've done it.

How DEEP is the cavity you could put the cargo into? With no carbonates and a little bit of overcooking, I made a cake that would be sufficient for you, lasted 35s.

[jackssmirkingrevenge]

You could always cut up a 9V battery and use the mini cells inside (after checking which brands use the cylindrical ones of course )

Won't work, AAAA size is 8mm and there's that pesky threaded rod to deal with, the cavity is 1/2" as MrC already measured (and we know was drilled)

Or even use a charged capacitor, it only has to work once.

Hmmm... now you're talking...

Pretty hard to pronounce in most cases, in French, "Fussskingeurrr" ?

I'm relying on the fact that most English speakers would just read that as a "c"

[Ragnarok]

Can I point out that projectiles are essentially in freefall for the whole of their flight, and there is a slight problem with using level switches in freefall?

[saefroch]

The cake mix will not be able to deal any significant damage to the projectile, even if you were to adjust them recipe to be more sugar-heavy (the heat capacity of all that metal is just too great, the worst you could do is ruin any heat-treatment). The addition of a carbonate should prevent any real damage because it reduces production of gaseous products, and sort of halts the reaction halfway.

Do some testing in a comparable container with cake mix first. Don't grind it, just pour the sugar solution into the form as a liquid, the viscosity can be comparable to that of water if you turn up the heat right before pouring. If you plan to reuse the miniboy, you'll need to clean the cavity, because if nothing else the mixture will deposit a hard white substance that I suspect to be primarily K₂O.

[POLAND_SPUD]

not to be that d### who is always saying 'told ya!!' but
I told you!!

you should have chosen a design that is cheap and easy to produce