long range ammo MiniBoy Mark I

[ramses]

... unless the thing detonates in the barrel

Implying R Candy experiences a shock wave. Tut tut JSR, I thought you were a man of Science.

Even if it ignites in the barrel the only side effect would be some residue in the barrel.

MrC, how much experience do you have in chemistry? I'll give you a synth that'll increase the flour output by a metric s***ton.

Not white phosphorous, I hope?

If you fire the dummy projectile straight at the ground, be sure to add weight to achieve the same sectional density.

I think you're making your cake with a little too much flour. I believe even candy propellant calls for a richer than stoich. mix.

[jackssmirkingrevenge]

Implying R Candy experiences a shock wave. Tut tut JSR, I thought you were a man of Science.

Even if it ignites in the barrel the only side effect would be some residue in the barrel.

I was clearly making light of the typographical error as opposed to actually suggesting ordinary cake mix was capable of detonating

[Fnord]

Hey JSR, don't worry. Everything from cake to a bad toupée is capable of undergoing detonation in the hands of a sufficiently experienced SF member.

Anyway, can some type of organic dye be used to give the smoke color? I've gotten mixed answers from searches. White smoke on sand/sky is kinda hard to see.

[MrCrowley]

Yeah we had discussed organic dye a little earlier (I don't blame anyone for not being able to follow every detail of this endeavour), I couldn't find what the organic dye was actually called and where to find it. Also, Guy Fawkes is a few weeks away and I can buy coloured smoke bombs (and proper fuses) for pretty cheap. Figured I'd mix them with some homemade cake and see how it performs.

[Fnord]

Oh, yeah. I saw that post but forgot about it for some reason. My bad.

[jamie e]

Sweet thanks bro. Got a cannon 40D SLR, good for photos but doesn't take video:(

[warhead052]

Sweet thanks bro. Got a cannon 40D SLR, good for photos but doesn't take video:(

Uh what? That's pretty off topic I think.

[MrCrowley]

Sweet thanks bro. Got a cannon 40D SLR, good for photos but doesn't take video:(

Uh what? That's pretty off topic I think.

Yo Mr.C any chance i would be allowed to come and watch or help out with the launch?
i only just realized how soon you planed for it to happen and its a once in a lifetime thing to see.
I live in Auckland, i have a car and licence and i have about 4.5kg of KNO3 witch i believe to be one of the parts to this 'Cake' you speak of, and very willing to donate for this.

Yeah you could probably come, don't think my friends would mind. The launch date will be somewhere around the 20-25th of November up at Mangawhai. I'll probably be able to tell you exactly what day I'm planning to do it a few days before then and hopefully nothing goes wrong with the cannon while I'm up at Mangawhai as there's not much I can fix while I'm up there.

If you're able to drive to Mangawhai on a week day with about a day's notice of when exactly I'll fire it, there's no reason why you can't come. I wont be needing any more KNO3, thanks for the offer though. If you have an HD camera, bring that

[warhead052]

Ah ok, didn't see that before.

[MrCrowley]

I can get 50mm O.D. steel pipe with 1.5mm walls that is "food grade", which apparently means it has had the seam ground down but does not qualify as seamless tube for pressure applications.

Wall thickness too thin? Apparently T304 steel is used in the food industry (no idea if this is the same type as the pipe specs above) which would give the pipe a bursting pressure of 4000PSI but another type of steel (think it was T316) has a bursting pressure of 1000PSI for the specs above.

[jackssmirkingrevenge]

316 is normally used for marine applications due to its greater resistance to corrosion (also currently lives in my eyebrow and nipple ) but to my knowledge is more expensive so it's likely 304 you're dealing with. Worth checking exactly.

In any case, burst pressure of 1,000 psi sounds a bit low for stainless pipe of not inconsiderable wall thickness.

[MrCrowley]

304 it is. He's selling a 430mm length of 100mm diameter tube with 3mm wall thickness for $40NZD so hopefully a 1.5m length of this 50mm stuff will be less than that and not too much more than $20 worth of fibreglass.

If the metal backing on the MiniBoy is too large for the 47mm I.D. tube, I'll probably just replace it with a smaller washer and sound down the plastic components of the sabot. Better than buying 63mm O.D. tube and having to make the sabot larger.

Edit:

The guy wants $60 for a 2m length of the pipe and $15 for overnight courier. The good news is that the O.D. is actually 50.8mm so the I.D. should be 47.8mm, perfect for Miniboy and the working pressure is 900PSI with a burst pressure of 4500PSI.

$75 for a barrel...fück

[POLAND_SPUD]

$75 for a barrel...fück

ohh come on... can't get a seamless pipe in NZ ??

Find some welder/company/machinist/whatever call him and ask 'excuse me where can I get a cheap seamless pipe'

[jackssmirkingrevenge]

Find some welder/company/machinist/whatever call him and ask 'excuse me where can I get a cheap seamless pipe'

He would be from New Zealand and not understand.

$75 for a barrel...fück

Quality metal is expensive. Deal with it

Besides, does it have to be stainless?

[MrCrowley]

I've been a naughty boy, found a different supplier that was a lot cheaper but a little riskier (for a starters, the guy didn't speak great English).

He says the tube is S/S and doesn't list the grade but because the outside diameter and wall thickness is identical to the other pipe, I'm certain it is the same hygienic 304 grade steel as I did some research with NZ suppliers beforehand emailing them for quotes and the only pipe they had with the same dimensions was the 304L food grade tube.

I'll have to ask him for the specific grade when he replies to my emails.

This stuff is costing me $40NZD for 2m plus $10 postage.


Edit: Grade confirmed as 304. Again, not seamless tube but the inside is smooth so it appears to be the same as the other stuff.