White lightning propellant Question

Why does WL propellant swell and get 'crusty'? I compared WL and BT slugs(24mm reloads),and the WL slugs had swelled and had that white crust on them,the BT slugs were unchanged.

One absorbs moisture much more efficiently due to the nature of the chemicals used. Just a guess though.
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Magnesium to Magnesiuim oxide.

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Thank you,Jerry.

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I forgot to ask;how's that affect the propellant performance? (MgO instead of Mg.)

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MgO "stabilizes" the burn just as well. it reduces the smoke very slightly (no way you could detect it).
The main "problem's" are dimensional change and hard to ignite surface.
The tight grains can be solved by taking off a thin layer of paper. The surface can be sanded down.
Both are "manufacturing" issues and should rightly be treated as warranty issues.
Jerry

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These have been stored a long time after opening the original packaging. I would not dream of trying to turn them in a warranty claim.
I wonder what would happen if MgO were used in manufacturing instead of pure Mg;would it eliminate swelling(at the cost of more difficult to ignite)?

Jim Yanik wrote:
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It wouldn't be "white lightning".

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Really?
The "white" output is indeed MgO.
Thank you once again for demonstrating your knowledge.

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David wrote:
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You're welcome.
See, civil chat IS possible.

Would be curious to know why they would want to add MgO; however adding Mg could have the effect of adding small quantities of MgO as an impurity. That material could then combine with the NH4ClO4 to produce Mg (ClO4)2, which is so hygroscopic, it is used as a desiccant.
-Larry (That, combined with the atomic fallout in the atmosphere...) C.
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Which is likely what is causing the caking and expansion of WL grains over time.

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WL seems to be more sensitive to humidity. They do fine until you open the sealed pack. I've had a couple grains swell so much they would no longer fit inthe liner tube. One from a 3-pack of E18s I gave to the local Fire Dept inspectors who checked out my stuff to take back and burn in their burn pit.
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kaplow snipped-for-privacy@encompasserve.org.TRABoD (Bob Kaplow) wrote in writes:
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Mine have been stored in closed ziploc bags inside a second,gallon-size ziploc bag,inside my closed range box.(Humid Florida,of course) I didn't think that much moisture would get to the slugs,inside those ziplocs.I had separated them to make individual reload kits from the 3- packs.
The slugs are inside the liners,and they don't slide anymore,and the exposed end bulges slightly,and I see that the slot has partially closed.

Would suggest adding little silica gel packets from, say, vitamin bottles and such.
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The best oxidizer in the package is the apc. You coul probably store them in dry nitrogen and eventually run into the same problem.
What about storing in a fridge or freezer? Lower temp should reduce oxidation rates by a factor of two for every 10 degrees C the temp drops.