Factory blanks are occasionally obtainable but hard to find. I don’t see blank ammo outlined in any from the countrywide catalogs that listing Reside ammo. Now and after that Aged Western Scrounger has a number of but not in each individual caliber. Navy Arms sells 5 in 1 blanks but https://strapweaponshop.com/product/triple-r-munitions-223-5-56-nato-blanks-100-rounds/