Does anyone know what powder to use in .22 lr blanks. I have made a star crimping die that works well and closes the top of the cartridge perfectly but I cannot find a powder that produces a loud report. I am using these to propel an arrow and can buy special blanks but they are so high priced that they are like gold and want to make my own. I have tried EC blank powder but that only produces a weak pop. Have also tried bullseye and a couple other fast burning powders and they are no better.

I think smokeless powders requires the building up of high pressure inside the firing chamber of a gun in order to burn efficiently (to get the loud bang) other wise is just burns.
I think a fiber over powder wad plus the star crimp might help by taking up space in the blank case there by allowing pressure to build up.
Or try old fashion black powder it is efficient at much lower pressures.

Trying to propel an arrow? What weight is the arrow? How fast do expect or want it to go?
These are the questions that might help determine if a 22 cal blank can make enough energy to meet your requirements.

Sounds like a fun experiment, also sounds illegal. Remember its all fun till someone looses an eye. Be careful!

Years ago I remember seeing a picture of a shark repeling pistol. I was all stainless steel and was build on the old 6 shot pepperbox revolver concept.
It fired darts about 7" long. The dart actual stuck out the ends of the barrels and were propelled by 38 special or 357 mag cartridges with the darts crimped right into the cases.