Tested a Couple Shells

[cmjlab]

Tested a couple 4" shells yesterday.

 

4" Report Inserts Shell

https://www.youtu.be/et4UBWSSXJ4

 

4" Chlorate Blue to Firefly (sorry for kids commentary)

https://www.youtu.be/gDTsbFOSJaI

[Richtee]

That report shell was nicely timed. Bravo! How big was the bottom?

[cmjlab]

Thanks, there's a few kinks to work out, like the ring of reports that didn't leave the center and the sloppy 3rd ring. I don't think I shimmed them well enough.

 

Bottom Shot: 3.5" finished size, with a 2.5 ID. I hand rolled that one via Fulcanelli (but with RamBoard and Virgin Kraft liner)

[WonderBoy]

Nice shells cmj. The report inserts sounded pretty crisp.

 

Was the second timing at the end of the shell casing? And did you pipe fire to the middle of the shell or just at the end? I have seen something like that happen in longer shells before, potentially from weaker burst or lighting from the end. The shell breaks open like a banana peel and the inserts at the bottom of the casing can get stuck.

[cmjlab]

Well I tried to pipe fire to the center of the shell by extending the spolettes with a couple turns of paper, by I punched vent holes at the few places I tied it into the black match (pretty much where the inserts were). I think what happened is that fire pretty much got into the burst right at the top of the shell because of the vent holes i made, causing the 2d timing to not spread at all because they were at the opposite end of the very long shell (like you were describing).

 

I hadn't considered a weak burst but couldn't rule it out. I used 32 longitudinal each spiking (along with enough horizontals to make small squares). The B.P. I used to break is the same I used to launch, and for spolettes (I realize that doesn't help tell how good it is), but my spolettes burn consistently at 2.4 - 2.6 sec per inch when pressed, and the burst used 1 oz per pound and launched the shells pretty high. I could try a booster next go around, but I was concerned the bottom shot wouldn't light ( ask me how I figured that one out on my own!).

 

Charles

Edited March 16, 2023 by cmjlab

[WonderBoy]

The longer the shell is, the harder it is to get nice breaks. Did you fill the entire center with burst or use a canulle? I know it may not be considered "traditional", but I personally break nearly all of my shells using polverone with a booster. You need to be careful not to over do it, but it can definitely work well. Just watch some Italian shell vids and you can clearly see they're flash boosted. Not saying booster is necessary, but whatever you do, you want to try to spread fire through the whole shell as quickly as possible. A trick I learned from an old AFN video was to drop in a stick of blackmatch that runs the length of the shell.

 

Another potential option is to put a layer of BP or polverone in the bottom of the casing before loading the inserts. It won't really help with the break, but it will keep the inserts from sticking. If you go this route though, be sure to fill everything very solidly, you don't want to add a compression point.

Edited March 18, 2023 by WonderBoy

[cmjlab]

Yeah the black match I used to make the spolettes ran the length of the shell, with the intent to stop the paper extensions at the center of the shell where the 3rd timings were located (two rings), and have the first spit of fire at the center of the shell.

 

Just picture a normal Spolette, with 10" long black match strands, nosed / tied / vented like normal. Then I took 5" long strip of Kraft paper and rolled it over the black match so that half of the 10" of black match was piped, bringing it to the center.

 

I filled the entire center of the shell with 2 and 4 Fa B.P. (though it wasn't much in the center of the shell where the 3rd timings were because I used 3/4" inserts there (the first two timings were 1/2" or 5/8" inserts). Talking this through, I'm starting to see why it looked like a bowtie in the center, lol.

 

I will work on the shimming the inserts correctly for now, and getting the spolettes piped correctly too. I think that alone will help. I also plan to use 5/16" inserts and 1/2" inserts in the next 4" shells, that way I have more inserts to hide the slightly off timings.

Edited March 17, 2023 by cmjlab