What is a 223 black rifle anyway?
There has been ooodles of discussion on various sites about intermixing 223 Remington and 556 NATO. Most OFB you buy will be .223 unless stated. It will be most likely military crimped so the crimp has to be reformed/removed to prime. There are subtle differences between the 2 cases so my rule of thumb is I don't mix.
I load my .223 brass with RCBS Gold Medal Match Dies, not bushing dies, one step below bushing dies on the FL and NS dies but with the Competition bullet seater. I like the RCBS Comp seater because it is set up to take a bullet from the front instead of the bottom and 22 caliber bullets aren;t all that big. Easier to drop in and seat that put in the bottom and pinch your fingers... plus the micrometer head makes setting SAMMI specs and repeatability easier.
I use Hodgon powders and CCI primers and Hornady 55 grain HPBT pills.
Keep in mind that like the big calibers, the 223 is a bottleneck and as a bottleneck it will exhibit all thje characteristics of it's big brothers like case elongation, neck cracking and pressure signs around the case head. You have to trim to length regularly and anneal if you want then to last. I don't anneal the Federals but I do anneal the Lapua. The Feds are tossers anyway after the 3rd reload.
Hope that helps probably I just muddied the water some more.......