Can't say I've heard of any of the non-magnum CZ550s splitting stocks. Keep the action bolts tight and it shouldn't be an issue. If you bed it, don't be tempted to fill in any gaps behind the trigger guard or the tang of the action. I put some spare left over bedding compound (from when I bedded the action) behind the tang on my 375H&H mag and the stock did eventually split there - my fault.
They deliberately leave gaps in these areas on magnum calibres since the metalwork does actually move in this area under recoil. I wouldn't expect this sort of issue with the 30/06 though.
