Ah. Tried to fix something yesterday and broke something else. Should be fixed now.
Primer Seater - yes, I think it's just a case of me needing to seat them better. I was initially a little 'light' on the press - mainly because I haven't done many of them. However, will also look at primer options. Recommendations? Also, if I change primers, will I need to restart the testing? The next lot are already primed and ready to go.
Barrel cooling. Yes. As you stated. Though in hindsight, should I probably not allow it to cool between each shot? I realised afterwards that the end of the string would always be hotter than the start. I might need to take a book down to read between shots!
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