Well this has been interesting....sometimes.
The very first mistake I see in this whole thread was at the beginning. The brass was an unknown. How many times fired, how was it re-formed, how many DIFFERENT rifles was it fired in and so on. Brass of unknown origin/use is always a problem and IMO should be fully resized so they are all the same.
Had I been faced with this I would have set up the RCBS die to cam over slightly when sizing. I would then have done a test for incipient head separation (an easy test with a paper clip). I then would have culled the suspicious ones.
I then would have fired them in my chamber with a good stout load (not max!) I would not even be looking at groups at this point, just trying to get the brass to my chamber dimensions. I would then check again for incipient head separation. Any cases that failed this test would be culled.
I would then check them all for trim length to make sure they were all under spec. I would NOT trim all to same length at this time, just make sure every thing is under max.
I would then use CatShooter's method to find proper fit. He has eons of experience with the .220 Swift.
This can be done quite easily without the Hornady "headspace gauge" if you remove the firing pin from the bolt. Once I determined the proper place for my die I would run all the cases through and I would make sure that that die was locked tight (I like the cross-bolt locking rings YMMV) I would then try to trim them all the same length. If any were short of recommended minimum I would find the middle ground and trim accordingly as long as none wind up past max. The short ones will probably catch up at some point during the life of the brass.
Now I would have a good starting point. I would then pick ONE bullet type and ONE powder type and try to work up a load from there. I can't possibly tell what a rifle is going to like by jumping around with a bunch of different loads and bullets. That's not to say I don't take different loads and different bullets to the range at the same time but I keep careful notes and always use separate targets. I also clean frequently.
I feel that if Swift4Yotes had followed this procedure I have just described we would not have 7 pages of sometimes helpful responses and sometimes nothing but vitriol. I will say that I was deeply offended by Eric's comment about CatShooter's helpfulness. In my experience CatShooter has always tried to be helpful ESPECIALLY to young re-loaders who don't have the knowledge or experience that some on this forum exhibit. He also solved the OP's problem. JMO
Swift4Yotes, If you are going to ask for advice on this forum I suggest that you at least try the suggestions put forth to you instead of continuing to head down-hill on that same out of control red wagon you've been riding in. Just my own observation after re-reading this thread 3 times.
