In carrying out 223 blanks I dimension and key case as normal. I take advantage of concerning 7 and 8 grains of Pink Dot. That offers it a good loud noise which is consistent. I make use of a C H crimp die to finish it off. Occasionally the shoulder https://strapweaponshop.com/product/triple-r-munitions-223-5-56-nato-blanks-100-rounds/