Spring thunder shell that has 17/32 brass / 5/8 tube as the barrel and the OD of the Flak Demolisher Post. 

Should work In the breaking wind, flak and foam of nature, maybe more as well. 

Can't test the shells as I don't have any blasters with the ability to use shells. 

Requires a 17/32 brass tube or a 5/8 OD tubing of some kind. Cut length to the end of the shell. Sand if tight. Use e-tape or adhesive if loose. 

Remix of [https://www.thingiverse.com/thing:3210080](https://www.thingiverse.com/thing:3210080) and [https://www.thingiverse.com/thing:4562212](https://www.thingiverse.com/thing:4562212) .