Tannerite went poof not Boom: How to fix?

[TXAZ]

Had 1 lb of some year old tannerite I thought was good. Opened the bottle and it was hard crunched it up, mixed it, hit it with a .50BMG at 100 yards, went poof not Boom. One guy said it had absorbed moisture.
The plastic bottle was mostly intact slightly shredded and all tannerite was gone.
I have one more, any suggestions on how to get the next one to go BOOM?
Can I gently warm the white beads unmixed or ???

 

[T. O'Heir]

"...a .50BMG at 100 yards..." That's probably your issue. Might be too big at the wrong speed. However, the stuff supposedly does such moisture out of the air and harden into a single clump.

 

[TXAZ]

Not too big and well over (@2800 FPS) the minimum speed.
Done it before same distance.

 

[geologist]

It sounds like the ammonium nitrate prills have absorbed moisture. I would put them in a sealed bag with a moisture absorbent pack.

 

[MagnumWill]

That would be interesting. I’ve got some year old stuff as well, i’ll have to try it.

 

[Double Naught Spy]

Yeah, we did tannerite at 500 yards with Barrett M82A1s at a class I took. The .50 will work just fine.

 

[Mike Irwin]

"One guy said it had absorbed moisture."

That's your answer. The fact that it was hard and blocky means that yes, it drew moisture, and there was likely still a lot of moisture locked up in the ammonium nitrate, which made it burn rather than explode.

The only way you can fix it is to keep your tannerite from getting damp.