Which matches would you make?

I have two rifles: A Texan .457 Carbine CF, and a new Marauder SAM .22. I have two scopes: A Hawke Vantage 3-9x40 and a Hawke Vantage 4-12x50. Both IR. I had the 40 on the Texan and just purchased the SAM and the 50.

I use the Texan for hog and deer hunting, often in the swamp bottoms, and often at first and last light. The new SAM will be one of my small game guns - mostly squirrel in the oak bottoms by the river, but not usually at dusk or dawn. Neither place is bright light most of the time. My intention had been to transfer the old 40 to the new SAM, and install the new 50 on the Texan. My thinking was that since I often use it in the waning light, the 50mm Obj. would help gather more light and maybe give me another 10-15 min of hunting light - which can make a difference with deer. But then I started second guessing myself, and wondered if the greater magnification would give me better shots on a smaller target, so should use it for squirrel.

Now I am waffling back and forth, so decided to seek some opinions and reasons. So, which combinations would you make and why?
 
Never hunted in swamp land but here in the mountains I have had deer come up right on top of me quite a few times. And that’s why I always kept my scope set on 3 power. You don’t want to fiddle with your scope with a deer right next to you but if there’s one far away it’s easier to adjust up.I can only imagine that in the swamp land the shots would normally be closer.My 40 diameter scope drawled in plenty of light right before dark.
 
The objective doesn't matter in this case. Both will give 100% light transmission. You cannot transmit more than 100%, just not possible. I think both scopes are too big for the purpose though. I use a 1-4x20mm on my Sam Yang for close range pigs. Best to not have to mess with the adjustable objective.



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I agree completely on using low power for deer. I shoot in Sierra Nevada forest and 3x has cost me deer several times. I simply cannot track deer at close range moving fast at any magnification. I shot my deer this year with a hawk vantage the 2x7 model and even the 2x was a bit too much. I almost missed it. I looked through my buddies scope at dusk tho and he had a thousand dollar scope 30mm tube 3x9x50 if I recall and it was much clearer and gathered more light. I think you would be fine with either scope but with deer I'd go with the 3x or go buy a 1x4 or 1x6. I have moved all my deer hunting scopes into lpvo category. 
 
Thank you all for your input. But this is what I have and can't spend any more at the moment, so let me rephrase the question: Which combinations, with the scopes and rifles I have, would you make and why?

For better info, the South Georgia swamps and river bottoms can very greatly in on ground terrain. It can be very thick and hard to nearly impossible to pass through in higher elevations (and I mean a change of only a foot or two above water), and then suddenly open up into an oak bottom or cypress stand where the ground under the trees is nearly bare and shots through the trees over a hundred yards are not difficult. But almost universally it is dim due to the heavy canopy overhead. Any spots where bright sun gets through are so choked with undergrowth that they are impossible to traverse.

" I would PERSONALLY buy the 2-7x32AO Hawke Vantage on the classifieds for $60 shipped. "

I may do that just to have it at that price. I have that scope on my Gamo Urban and like it. I am usually on 5-7 power for squirrel, depending on how far up in the canopy they are.
 
I would use the larger objective lense scope on the Texan and the smaller on the short range Sam. You will likely be target practicing at longer distance with the Texan and with the larger bell and more magnification you will have a slight benefit there. Hunting at 4 power won't be bad either, even at close range. Also, tracking squirrels at 20-30 yards in the trees will probably not be as easy with a higher power scope.