UPDATE:
Due to the excellent input, I have ditched the rain rifle idea, and "moved" to the Marlin 336 solely to the homestead defense rifle role (which works well for me since I have no semi-auto / ARs left any more). And thus, have also ditched the idea of a Puma 92 in .454 Casull (even though it's lighter than the 336, and even though the consensus seems to be that it's more terminally effective than the .30-30 to 100 yards - which I tend to agree with).
So, I'm gonna stick with turnbolts, period, for all big game hunting (except maybe the .357 max Contender from a tree stand). Thanks JMR & others, for the reality check. I will just "deal" with the scope fogging issues, and take all the advantages of a bottlenecked turnbolt (mainly the extended range, but also the lighter weight, easier to clean and "de-moisturize", etc.).
Besides, the Marlin isn't all that light anyway. And not to mention, that I prefer to hunt with archery equipment anyway. And not to mention, I am worse and worse with iron sights with each passing year, let alone how they'd work for me in the rain, which was the point of the rain rifle idea to begin with. I guess it's time to invest in Butler Creek flip-opens.
Relatedly, I just scoped the 16" Marlin 336 with this scope (rather than the FXII - 2.5x fixed) - I like this reticle - it's pretty slick - nice scope @ $230 plus tax:
http://swfa.com/Leupold-1-4x20-VX-1-Hog-Scope-P51848.aspx
The eye relief is around 4.25" on 1x, so it works up to about 2 power (which is perfect) even "semi-forward-mounted" on a rail/peep sight combo unit, on top of the Marlin's receiver, if you mount it as far back as it will go. Leupold QRW rings, with the rear peep unit (Williams) and small screwdriver in a sandwich baggie inside the nylon buttstock cheeck piece / zippered pouch doohickey - for a BUIS.
P.S. It is somewhat confusing / difficult to fully research this scope, since it appears to be named the "VX-1 Hog" scope in some places, and simply the "VX-Hog" scope in other places on the net.
P.P.S. Can we all at least agree that the cheap press-checkering found on the new Remlins sucks? Ugh. Remington is definitely destroying Marlin. I don't think it will come back to quality now. Get some old Marlins while you can.
