I use an old RCBS Taper Crimp die for my 223 (5.56x45) loaded rounds.
Do not roll crimp.
Taper crimp to smooth out & uniform neck imperfections only for smoother feeding in semi-autos.
And use a Small Base die when resizing.
Not required - but works for me, many thousands of rounds with no problems.
Taper crimp does not require exact case length like a roll crimp.
OldmanFCSA = "Oldman" at www.fcsa.org
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