I just won a new Thompson Center Encore 300 Win Mag (paid $40 in rafle tickets) and am now doing some research on scopes.  I already have some nice scopes (Kahles & Swarovski) on two other rifles.  I think I have decided on either the Zeiss Conquest (1" tube) 3.5x10x50 or the Meopta Meostar (30mm) 3x10x50.  I can get the Meopta for about $200 cheaper ($549).  What is the difference/advantage to the 30mm over the 1" tube?  

I also was wondering about 1" as compared to 30mm. Is it because they come from Europe vs. US ??

actually the 30mm scope will gather more light than the 1"

Go with the Zeiss it is a better Quality.

Not trying to be a smart*ss, but the difference is 4.6mm. 1" = 25.4 mm

All this means is that the the 30mm tubed scopes can gather and hold more light. And yes, they are usually all metric because these scopes are most likely imported from Europe and Asia. Most high end and specialty scopes are built on the 30mm size.

there is no real light gathering advantages between a 30mm and 1" tube.. gathering more light has more to do with the quality of glass and the coatings on the lenses.

yes one is European loll but even some higher end target and long range leupold's have a 30mm tube..

the biggest and really only difference is a 30mm has more wind/elevation adjustments.