Sciencemadness Discussion Board

Sensitize Nitromethane for a rifle bullet round?

bb911gt4 - 25-12-2013 at 06:05

Hey guys,
I'm new to the forum and I was wondering if anyone has ever been successful in sensitizing Nitromethane to detonate with a rifle bullet round.

I've played around w/ Ammonium Nitrate/AL mixtures and had a blast.

Thanks!

gnitseretni - 25-12-2013 at 08:11

Not sure if it's bullet sensitive (I used a detonator), but I've successfully detonated NM sensitized with Microballoons that I found at a local hobby store. Don't quote me on this, but I think you only need like 1% by weight microballoons.. which is not a lot in "weight" but is in "volume" because it's so lightweight.

I have a 30-06 and plenty of NM, but no microballoons. If I did I would've tried it and let you know.

There are other ways to sensitize NM, but again, I don't know if they're bullet sensitive. You can sensitize NM with Amines, hexamine, Nitric acid, etc. But I think microballoons is probably the easiest to find.

bb911gt4 - 25-12-2013 at 09:31

Ok,
Maybe I'll give that a try. Any idea what size microballoons are best?

How do you think this would compare to AN/AL mixtures?

I'd really like to hear from someone that has had a successful mixture before I start spending cash.

bb911gt4 - 14-1-2014 at 10:15

Hey guys,
So here's what I tried. 74% Nitromethane, 5% microballons, 5% Hexamine fuel tablet (from ESbit), 16% aluminum powder. I shot it with a .223 from about 20 yds. There was no detonation. Any suggestions?


Ral123 - 14-1-2014 at 10:28

NM is one of the most insensitive materials. It's so insensitive it's sold freely. It's like cast TNT. You want to make something that requires 400g pressed TNT booster bullet sensitive.
Here's what you do: freeze the NM, crush it to micro crystals and mix it with micro magnesium particles. Then shoot with no less then .50 BMG

bb911gt4 - 14-1-2014 at 10:49

From everything I read, NM can be made cap sensitive w/ aluminum, amines, or microballoons. It seems that cap sensitive and rifle sensitive are not too far off from each other.

Ral123 - 14-1-2014 at 11:06

There's somewhat of a difference between a pointy lead slug at 750m/s and a gram well pressed PETN and lead azide in thin aircraft aluminium with Gurney velocity of 2000m/s+ not to mention the extreme heat.

[Edited on 14-1-2014 by Ral123]

Dany - 14-1-2014 at 11:17

Quote: Originally posted by Ral123  
grunny velocity of 2000m/s


It's Gurney velocity, not grunny nor granny!!!!

on what Gurney velocity are you talking about???

Dany.

Ral123 - 14-1-2014 at 11:33

It was about time someone to hard critique me. I was talking about the speed of the aluminium particles and gases that the cap will generate if the case is reasonably thin walled.

bb911gt4 - 14-1-2014 at 12:00

I do have some powdered magnesium available. Do you think this would be better than the aluminum?

Do you guys know of any other good exploding target recipes?

Ral123 - 14-1-2014 at 12:07

But it was a joke. Anyway about that recipe. So you need some chlorate and red phosphorus. And a bunch of spare body parts :D. And there's always the classic Pb3O4/German dark.

hyfalcon - 14-1-2014 at 12:15

copper oxide and aluminum powder works along with standard 70/30 flash.

Rosco Bodine - 14-1-2014 at 19:35

http://www.boomershoot.org/general/Nitro.htm

bb911gt4 - 14-1-2014 at 20:26

I appreciate the references to other ways to sensitize Ammonium Nitrate, but I'm really looking for something different.

I could easily pick up some aniline to sensitize my NM. Does anyone have experience with this?

Turner - 14-1-2014 at 21:12

I don't know what you do or don't have access to, rifle detonating explosives doesn't sound like a lot of fun to me, I'd just stick with your AN/al charges.

You might try adding anhydrous nitric acid to your NM, this may or may not be bullet sensitive.

Pard - 15-1-2014 at 14:25

Is possible you just want to do reactive target or is it imperative it must be sensitized mix. Otherwise you could have a layer on outside.

You say you had a blast with ammonium nitrate / nitromethane. I of understand it was not bullet sensitive. Though I've been told the reactive target mix / tannerite mix was just ammonal. Surely if that works, then NM wouldn't make it less sensitive. At what distance does .223 achieve terminal velocity? maybe 20 yards was too close or far.

Scientwisted - 17-1-2014 at 15:00

The "terminal velocity" of any conventional gun round is achieved the moment the bullet leaves the end of the barrel. From then on it is acted upon by wind resistance and drag and it will continue to loose velocity until it stops. As far as the NM for a reactive targets goes I'm stumped, I really believe that AN/Al is the most efficient and economical material for reactive targets and if you like the way that works then you already have a solution.

Turner - 17-1-2014 at 15:37

a bullet is intact traveling it's fastest approximately 10 feet or so beyond the end of a gun barrel depending on other factors.

bb911gt4 - 17-1-2014 at 20:33

Yeah, I thought about putting in on the outside, but really I'm looking for a simple target that is more powerful than the AN/AL mix. I don't really want to go through the hassle of attaching it to the outside every time I want to shoot.

Thanks for the suggestion though!