I'm not sure if anyone else will find this of benefit, but spent a little more time on the "range" with my unmodified CZ452 yesterday.
1. Winchester subs are OK, but not as good as CCI.
2. I've definitely had a bad batch of CCI subs. It was hard to close the bolt on them and groupings were not as good as usual with more fliers. Glad their gone!
3. I still can't make subs work for me beyond 50 metres. It's not just the drop, it's the groupings. Happy to accept that it's my marksmanship though.
4. Retried CCI mini-mags. What a cracking round in all senses! Point and shoot to 75 metres and good groupings, but bloody hell, what a racket. I couldn't get good groupings even with these at 100 metres, again happy to accept it's my marksmanship.
5. Can't really chop and change between subs and mini-mags, the zero is close, but not good enough for me. I was hoping to zero the subs for 50m, use subs most of the time and keep a few mini-mags on me for when a longer shot presented itself.