Making Day Shells
This is an experiment in making shells that can be shot in the daytime. These shells combine a small salute with simple carpenter string chalk that can be purchased cheaply at a lumber yard or equivalent. Click on the above picture and see three shots - each with a different time set on the time fuse. The first is normal time of about 3 seconds, the second is about 1.5 seconds, and the third is just over 3 seconds. With this setup, it seems that lower is just a bit better so a 1.5 second delay would be better than 3 second delay.
Buy some carpenter string chalk - it comes in several
colors. If you buy a large container, it is quite cheap.
Put a time fuse in a hemi and surround it with a flash
bag. The flash bag is just a gummed tape tube that
is filled with flash or whistle (flash isn't as smokey). Seal
the flash bag. The one in the photo was sealed with a
chipboard plug and hot glue. The bottom was thoroughly
sealed with hot glue - the chalk is inert and will ruin the
break if it mixes in with the flash/whistle. It doesn't matter
how hard you break them so put a big boom in, too.
Make up the number you need. These go quick so make
Put a cheap sandwich bag around the flash bag and
fill it with chalk. I use 8 ounces of chalk for a 4" hemi.
The sandwich bag keeps the chalk together and prevents
nasty spills - the colored chalk gets into everything if
Paste with anything to make the shell sturdy. In this
case newspaper and *slightly* diluted yellow carpenter's
glue was used. There are five layers of newspaper strips.
These take just a few moments to put on and make a
solid shell that is quite sturdy. Dry for a couple of days
Lift the shell medium to medium hard. It doesn't matter if it is at apogee when it breaks. These were 12 ounce shells and about 24 grams of 2FA were used to lift them. You can use Dixie cups for lift bags - the cups in the picture above were holders but I've used them to hold lift with good success. Put in the lift, hot glue in place. Fuse and enjoy!
Adding more chalk and making a bigger shell doesn't work well. A 4" ball shell seems about the right size. If you want more coverage, then use more shells. The reason for the 'unscalability' of the technique is that the chalk doesn't weigh much once it starts to disperse. The burst cloud essentially stops expanding after a few feet. So a bigger shell or harder burst won't result in a proportionately bigger spread. I shot a 6 pound canister chalk shell at a meet - it had over a pound of flash in it. The burst cloud was not much bigger than a normal 4" shot. However, all the car alarms in the area went off. ;-}