Originally Posted by
Bird
I have a couple of 307's. Plenty of brass available at a good price, and affordable jacketed bullets as well as plenty of options for cast. Probably the cheapest to shoot of the 3 calibers.
356 is expensive, and not a whole lot of ammo or brass around, and a more limited bullet choice. I have not done it, but 307 brass should neck up to 356 if needed.
375 brass is available from starline, and not too expensive. Selection of bullets limited.
I think you can get the top eject in the 375 only. The 307 and 356 were angle eject.