Jumpman2334
Jumpman2334
19 posts
Joined January 2019

I am not sure if I'm having sizing issues or not (223/556 on 550c)

I have a 550c. I dont have anyone to teach me how to load, so everything ive learned is from dillon and google-fu. i started with 9mm as i figured it would help me get the motions down. i think its paid off. 


fast forward to last night, i started sizing my first 223 on my 550c. the sizing die is the 223 rcbs x series die (regular, not small base), brass is all once fired LC sorted brass from xm855 and m193 cartridges (i got about 1200 rounds for free), and im using the hornady unique case lube. using the x series die, i have to size and trim initially, i then never have to trim again for the life of the case. i did this on purpose because i want to reload 223 in the same fashion i reload 9 (one pass).


here is the problem i am having. this reloaded ammo is going to be shot in multiple AR platformed weapons 100% of the time. having watched this video in the past:

https://www.youtube.com/watch?v=PIO37hANQlY 


it states the case needs to be flush with the lower mill mark for my intended application. my sized cases are between the min and max headspace (closer to the minimum i believe). the sizing die is already touching the shell plate so i dont believe i can go down any further. 


although i just watched the linked and around the 1:45 mark, it says 'it may be necessary to screw the die down an additional 1/8-1/4 turn max to reach minimum headspace.' it goes on to say this wont hurt the machine.  can someone please explain how this will not hurt the machine or die? i am thinking about trying this tonight after work, but im new to this, so its kind of daunting to willingly screw the die down further to the point that i know its going to be making contact with the shell plate. there is no way this can be good for the machine in the long term..?


i reload for volume. so i try to keep my machines longevity in mind. can someone please explain the reasoning behind this? 


thank you,

Brandon 
dillon
Administrator
dillon
3,110 posts
Joined July 2007

RE: I am not sure if I'm having sizing issues or not (223/556 on 550c)

When you thread the size die down past touching the top of the shellplate, you are taking any play out of the linkage and toolhead is all. This is common. We recommend only going down 1/8 of a turn at a time, then test the headspace.
Jumpman2334
Jumpman2334
19 posts
Joined January 2019

RE: I am not sure if I'm having sizing issues or not (223/556 on 550c)

Thank you. I turned it another 1/8 turn and that is all it needed.