Depends on your definition of medium size game, my idea of medium size game is 400-700 pounds. I'm assuming you're thinking more in line of whitetails.

Somewhere I read one of the original articles written on the 30 Herrett, and they did use the 110 gr "varmint" bullets, and found them to work well on deer sized game. I'd personally go with the 125 gr balistic tip or similar. I never did get a 30 Herret barrel, but always wanted to try the 110 gr Barnes X bullet. If you could eek 2400 fps out of it in a 10" tube, it would be a pretty neat set up.

Anyone out there tried either of these bullets and found that they would work for medium game.
How about zippy target bullets?