46 replies to this topic

[Creepin_pyro]

I'm thinking about ordering some grinding media. Just a little unsure as to what kind would be best (not for BP!) Any thoughts on the following list?

carbon steel, chrome steel, stainless steel, glass, zirconia, tungsten carbide, agate, sintered aluminium oxide, silicon carbide and hard porcelain.

Does anyone have any experience grinding Ammonium Perchlorate? Is milling needed, or would a coffee grinder get it down to a useable mesh size?

[Phoenix]

You were maybe looking for something a little more professional, but large quantities of marbles can be had very cheaply from eBay. Being glass, they should be OK for most chemicals. However, if they chipped (don't know if they would) then having flakes of glass in chems could be a cause for concern... Just a thought.

[Creepin_pyro]

So there are no special requirements for milling Ammonium Perchlorate? If not, I will just find the cheapest option (probably marbles)...

Edited by Creepin_pyro, 13 July 2004 - 02:24 PM.

[Dan]

i use to use marbles for individual chems (kno3, sulfer, charcoal, etc.) ihavent used perclorate or AP etc. tho. now i use a $12 coffee ginder (beware clean it really really good each time u use it or it will corrode expecially with oxidizers) and it works like 20 times faster. i already had one die on me. (do not use it for bp, i am sure u already new that tho.) for bp i just use .49 caliper lead balls for muzzle loaders.

Edited by Dan, 13 July 2004 - 01:53 PM.

[Creepin_pyro]

I've just got a little batch of Ammonium Perchlorate out from the mill....

IT'S ORANGE and there was a rather strange smell. I think there might have been some reaction with the media I'm pretty sure they were chrome steel, but they seem to have tarnished... Any ideas what's going on here? I'm a little worried!

[Richard H]

What is the milling jar made from? What have you milled in the jar prior to milling the ammonium perchlorate?

[Creepin_pyro]

The jar was a "Coffee mate" jar - I think HDPE, but I'm not sure.

I used a new one because I was scared of contamination.

I've milled Kn03 with the same setup with no problems.

So no ideas, then?

Edited by Creepin_pyro, 17 July 2004 - 05:11 PM.

[Creepin_pyro]

Well, upon further inspection of the media, it turns out that a single ball remains shiny and un tarnished. I think I may have purchased a single chrome steel ball, in a lot of other random balls. Whatever these are made from, the Ammonium Perchlorate has ravaged them - they seem extremely rusty, with orange and purple patches all over them. I think I need to be more careful about milling media, but I was never expecting this!

I'm still a little concerned about my orange powder. It seems to perform well, and no further reaction has occured, but I do worry about its storage. Any ideas what I should use to replace my dead media - I don't want to ruin another load.

[adamw]

How about ceramic balls, if you are absolutely sure that nothing else is going to be milled with them.

[Chaoticentity]

tried and true, I would use hardened lead media, any general gun store will have them for muzzle loading rifles. I don't know where exactly you'd get them in the UK but here in the US any gun shop/hunting store will have them in stock

[lord_dranack]

I don't know where exactly you'd get them in the UK

From a gun shop

Edited by lord_dranack, 20 July 2004 - 06:21 PM.

[paul]

Yes, here in germany for example you get 50 lead balls (17mm) for 12-15 euros. The price varies from shop to shop.

[phildunford]

Have not used these people yet, but they do lead balls by mail order:

Tal Arms

[BigG]

So there are no special requirements for milling Ammonium Perchlorate?  If not, I will just find the cheapest option (probably marbles)...

This was discussed before - using Marbles for milling media is a bad idea ? not to talk about the fact that they are not nearly heavy enough.

When looking at media you need to ask yourself a few questions:

1) Is it sparking?
2) Is it heavy enough?
3) Does it mill itself?
4) Will contamination from the media affect the chemical milled?
5) Will contamination from the media will effect the composition the chemical is in?


Of course, and answer of yes to one of the question does not necessarily mean that this media is useless. For example, sparking media can still be used to grind hard metals one their own..

Glass in general mill itself and the inclusion of glass in compositions has been proven to move the sensitive scale for certain compositions from ?not-sensitive? to ?very sensitive?.

Note that most Gun Shops in the UK sell very small media which is not suitable for milling. You need to look at ? inch balls and above, and those are not commonly used in everyday shooting. You are more likely to find such media in shops that deal with black powder.

Also, you need to check is the media is ?virgin lead? or hardened lead. Virgin lead has not hardener added ? and might disintegrate very quickly, although this apparently depend on the manufacturer. Some gain more density in the given area and then the ball is effective as harden one. I don?t know of a research on subject, this is just from personal experience.

Edited by BigG, 21 July 2004 - 12:38 PM.

[Creepin_pyro]

Thanks for that.... I had wondered about the safety of using glass, after seeing glass used in some of the more suicidal compositions out there - it does seem to act as a sensitiser.

I'm still a little confused about my metal media. The balls all appeared the same - shiny and reflective, yet most of them were destroyed by the AP. I just need to work out what the few that survived were made from. Can anyone to tell me the difference between Chrome, Carbon, and stainless steel in regard to milling/chemical compatibility?