I find these often very hard to chamber in my cz452.....really difficult to close the bolt, and then if you end up not shooting you quite often won't retract the seated bullet so have to discharge the gun just to eject the now spent case!!
However groupings not too bad...I managed 3 simultaneous 3/4" moa groups (actual range 50 yards) last week, but yes, as stated above you quite often get one that has a totally different sound to the others.....more often a louder "crack" than the normal muted sub discharge I find.
I had decided to persevere with them as I didn't like Eleys or RWS, but have