I believe those are PG-7VL warheads, which makes them 93mm.
The 40mm number comes from the fact that all RPG-7 rounds have 40mm bodies for their tubes. The warheads are usually over caliber of 40mm though, except for a few anti-personnel rounds.
The anti-personnel rounds that are 40mm are the same diameter as the tube. No HEAT warhead, but instead an HE payload with fragmentation around it. Essentially just a very long hand grenade. There are a few variations.
