Pretty green flames

I've got some professional chinese fiberglass mortars (3 inch) and after shooting about 14 shells from one, it developed cracks (small ones, they seem superficial). Are there any restrictions in using fiberglass mortars in cold weather (it was bloody cold for NYE), does cold weather compromise structural integrity of these mortars?

Thanks, PGF

I want to make some insert shells, for the first one I'd like to make a whistling serpent with report shell.
I trully have no idea on how to construct these whistling serpents with report, well I have a general idea but I don't know what the dimension of the serpent casing should be.

I was thinking along the lines of 10mm ID, 60mm long (could I shorten it to 50mm, having a little shorter "nozzle"?), 15mm of whistle mix pressed into the casing (leaving 30mm of the tube to act as the nozzle and the last 15mm will be filled with a small ammount of report composition and capped. Would this dance around the sky (and make some noise) or just fall to the ground with no sound?

PGF

I've got a formula that calls for -325mesh Bright aluminium (which is coated with stearin), now the binder is supposed to be dextrin, 5% of it. I've tried it and the finished stars are really crumbly, you can crush one with no problem.

I'm guessing that the stearin somehow inhibits the dextrin. Which binder is reccomended for stars that have a high content of stearin coated aluminium?

Thanks

Greets

So, I know the formula for normal KP is:

Potassium Perchlorate 70
Charcoal Airfloat 18
Sulfur 12
Dextrin 5

And the one without sulfur is

Potassium perchlorate 70
Charcoal 30
+5% Dextrine

Now, does anyone have any experience with either of the two? There is very little information on the net regarding these two so I was hoping anyone here could shed some light on the sensititivty, power and preparation (Screen and granulate/coat rice hulls?)

Thanks for any information.

Would anyone be interested in spirally wound canister shell casings. I would be willing to sell them for the price I get them from the manufacturer. The 2 main sizes I would stock would be 3" and 4" (2.5" and 3.5").

This is just preliminary market reasearch to see if it would be worth going into this because i'd have to buy several hundred of these casings and I don't need so many.

Please share your thoughts.
Thanks,
PGF