Re: more .223 rem qiestions?
Aside from seating and crimping, the very first step
Could be your problem. OAL, trim to length, crimping; it all comes second to actually resizing the case correctly in the first place. If the resizing die is not adjusted to push the shoulder back to proper headspace dimesions, you are best not going any further in the load sequence because they will not chamber or they will have excessive headspace and cause a very dangerous situation. Look further into properly sizing your brass, good luck.
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