Which Tyres?

Recently bought some Continental 25-32 Race28 W tubes to go with a new set of GP 4000S II tyres (28mm). As someone who's never had any major issues with tube/tyre combos before I've had three blowouts in the last week, one at speed which was pretty sketchy. I imagine the tube must be getting pinched somewhere but once pumped a little and rolled about I can't see any tube protruding. Any one had issues with this combo before? Might switch to Schwalbe tubes...

I've never used that exact combo, but equally I've never had any issues with Conti inner tubes and GP4000Sii tyres. Sounds like the inner tube might be getting trapped by the bead of the tyre. I've had a few explosive blowouts due to that happening, happily never while I've been riding them. I've definitely had blowouts where the inner tube was trapped between the tyre bead and the rim, even though there was no visible inner tube once it was inflated. One was sufficiently violent I ended up spilling my porridge, despite being in a different room.

What works for me is, after fitting the inner tube and tyre, to push the beads of the tyre back into the bead well in the rim, so that the rim beads are nice and floppy. That'll help ensure that the inner tube isn't trapped between the tyre bead and the rim when you inflate the inner tube. Then inflate away.