Harvester was the first can I bought. No telling how many rounds have been through mine. 223, 220 Swift, 243, 260, and 270 Win. Everything from 40 V-Max in the 223 to 145 ELD-X in the 270. It has never missed a lick, no issues.
Just a random thought here though. Do you think maybe when you got that end cap strike, that somehow it could have knocked the threads out of alignment on the can? You would think SiCo would have checked that when they fixed it, but who knows?
You have a really strange situation going on there. I will be following to see what the resolution is.