Most AR shooters around here won't reload the 223 F-C cases for whatever reason. I've never had any problem with F-C case in boltgun 223 and all the common 30 caliber cartridges.
+1
I have a bunch of FC once fired brass that I reload for my 223 bolt. Load closer to 5.56 spec about 3350 fps with 50 grain NBT. Have 3 reloadings on some without primer problems.
