[quote=jman221]
bore??? o.O sorry new to mech stats and everything...
[/quote]

A caliber can be directly converted into inches, and I think Tentacle's just trying to figure out whether you mean a 1.00 caliber sniper rifle (firing a bullet double the size of a .50BMG, which is the caliber used on anti-material rifles such as the Barret M107) or a 100. caliber sniper rifle, where you'd be firing a bullet somewhere around nine and a half feet wide (which honestly, IMO, is a bit large, since even large naval cannons that are mounted on battleships are usually only around eighteen inches, if I remember right).

EDIT (since I didn't see Asura's post): I prefer the top, black one, although that's simply only because it has less bits and as such is easier to see having good mobility. They're both solid choices.