Ramming Flares

[BlueComet24]

I recently got some strontium nitrate and have tried out a flare composition which produces a nice red without any metals. I would like to make flares that are properly compacted so that they burn more slowly and have more comp in the tube, but I'm not so sure of the safety of ramming a comp with Sr(NO₃)₂ in it. Shimizu states that "strontium nitrate alone does not explode even with a strong impact." I'm not sure about in combination with fuels. The composition I'm using is as follows:

Weingart Fusee #1

Strontium nitrate 16

Potassium nitrate 4

Charcoal 1

Sulfur 5

Wood meal 1

 

I don't have a press, so the only way I'd be able to get it really compressed is by ramming it into a 5/8" (16mm) tube. Would this be safe?

[OldMarine]

There's nothing in there to create a spark or severe friction. I hand ram Strontium red gerbs all the time. I don't use the press unless I add metals.

I think you're good to go. No more dangerous than a BP rocket.

[lloyd]

Patrick, it's less-sensitive than BP. Blue, ram away.

 

By all 'prudent practices' you should _always_ be wearing hand-protection on the hand holding the rammer, and eye protection.

 

But I've rammed lots of Strontium Nitrate comps without mishap, as has the rest of the industry. It's considered one of those "more gentle" oxidizers. Even more especially-so since you've stated a formula designed to burn slowly, rather than vigorously, as would BP.

 

Lloyd

[schroedinger]

Also you can think about using the rod and funnel method, where you press the comp only by hand force and use a slightly wetted comp to bind it. This method is also very fast.

[Arthur]

NO-ONE is going to state that a pyro item is safe -it's designed to burn! BUT that compound looks to be a reasonable risk to ram. Hand, arm and eye protection would be obvious PPE items.