A tricky one, Chris, without an underside to help. Assuming
carlinae is replaced by
cirsii in your region, and assuming you are within the rather restricted range of
bellieri (Foulquier's) I agree those are the only two species this might be.
I think most people would admit their experience of
bellieri is both limited and uncertain, so I for one hesitate to suggest absolute diagnostic features. Tim Cowles observed that in
bellieri the spots very often run outwards a little at the extrremities, as if the paint had run along the grain of the paper. This is illustrated in the picture below, which I believe is a mating pair of
bellieri:
If this effect is characteristic of
bellieri, though, it is not unique to it.
By default, and because there is nothing to suggest it is anything else, I suggest your butterfly is
armoricanus (Oberthür's). The discal region of the hindwing is perhaps weakly marked for a male but not excessively so and the second picture in particular looks exactly like
armoricanus.
Guy