i have both too...
for a smaller rifle with an eye toward light/compact, go 6x36.
for mid-sized rig built for precision, go 6x42.
i prefer the 6x42 optically, but i have no prob. runnin' the 3x36 on a hunting rig
It will be on a medium sized rig built for precision. It would be going on a semi-custom Remington 700, 24" barrel, currently weighing about around 8.75 with a 12 ounce scope. I've had some thought that I could lighten it with Talley lightweights and a lighter stock but realistically I might not make that change.
