Useful loads are in the 2000-pound range, with maximum tankage being about 1200 pounds of fuel, so you can pack 800 pounds of people and stuff into it and go for 8 hours to dry tanks at around 185 knots. Between aft baggage, nacelle baggage, and nose baggage, you can haul a lot of stuff AND a lot of people. Only the 310R produced from 1975-1980 had the long nose with baggage compartment.
The big split in 310s is the long and short nose varieties. This information was gleaned from conversations with DuPuis, some of the great info in Twin Cessna expert Jerry Temple's ' Temple's Tips' (there's a lot of info on the other Twin Cessnas there as well), The Twin Cessna Flyer's 310 prospective buyer page, reading the POHs (I posted a 310R POH PDF here), and lots of Googling and reading other articles from around the web. I'll keep the first post edited with any other information that is added/corrected.
We got to talking about this on another thread, but suggested that I post my 'brain dump' on 310s that I wrote up for my airplane partner, rather than wait for Jr to start a thread about it.
