Larry,
The flats of my V19 indicate 14mm bore, .551. Unless .001 counts as a backbore, it is very close to being .550, or, standard 28 gauge bore.
Chokes on this gun are about .009 and .019. Marked mod and full in English on the box and proof certificate, maybe more like mod and imp mod in real life.




My 12 has had some tampering with the bore, but, was marked 18.2 on both barrels when it was proofed.

Best,
Ted