45 Colt blank

I have a new unprimed case made by Top brass headstamped “45 Colt blank”.
Outside dimensions are the same as the standard 45 Colt cases.
What is the purpose of this cartridge and how is it usually loaded (better:hand-loaded,since according to me it exists as new empty case only)?

Starline (USA) makes .45 Colt Blank cases; these have a larger than normal Fire-hole(Flash hole) for better ignition of Black Powder used in Western Action and Western Films.
The Cases can be “handloaded” or machine loaded by Film Gun Suppliers;
A Normal multi-fold crimp (rosette) is usually used, but some blanks are made using a wad and just “rolling” the case mouth over slightly, and then lacquering the wad.

Star or Rosette Crimping ensures a loud noise, and complete combustion of all the Powder(whether Black, Smokeless or a duplex load.).

Starline also makes cases under “private” headstamps as well.

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