As far as productively adding to the discussion, here are few things I've done to help lighten up in addition to what Dave discusses in his article. YMMV, but this has lightened my load by well over 5 pounds:
-Carry only binoculars, as others have stated. A quality pair of roof prism 10×40 binoculars as your only optics is usually all you need. Any more magnification and things get wobbly w/o a rest. I wouldn't go lower than 8x, and rigging a simple 5’ piece of webbing for an x-back sling is a must. Great comments on glassing; besides being really dangerous, your field of view is far less than through binoculars of the same magnification. Save 3-5 pounds of spotting scope and tripod.
-Know your country. Hunting (and scouting) the same areas year after year let you know the places the animals use and those they don't; wild game are creatures of habit, though wolves and other hunters spice this up a bit. This is the best part of hunting in this manner: intimately knowing a place. You don't need a spotting scope if you have a good idea where the game is, though they are handy for unfamiliar territory or wide open country.
-Lighten your kill bag. Mine holds a polycro groundsheet, nitrile gloves, plastic meat bags (like garbage sacks w/o the toxic mold release agent), a knife, and lengths of reflective cordage. I bring a small ring saw when elk hunting. Love the Havalon Piranta, but am using a Helle Nying knife because my fingers have become quite cold intolerant. Save 10oz or more on game bags and other do-dads, plus all that bulk.
-Go gutless and bone out. Yes, there is a learning curve, but these two skills have transformed my hunting! The polycro tarp is very tough and lets you lay everything out to quickly bag and hang, so contamination, waste, and spoilage are nearly a non-issue. Save 20-50+ pounds in packing out bones, skin, and fur.
-x100 on Dave’s rifle information. My current rifle weighs in at 11 pounds, loaded. It was 13… got some more work to do! Should never have traded that Remington titanium 7mm-08 :(
-Shoot off your ruck and shoot offhand w/a sling. I used to shoot from a bipod and later a bog pod/tripod, but have gone back to the ruck. Now if you are reaching out past 400yds, this may not work for you. Keep your backpack cinched up tight and save 8oz to 2 pounds on the bipod or shooting sticks.
-Learn range finding by mildot. Everyone shooting further than 150 yards should have a mildot scope, right? Work out your shot dope and glue it inside your scope cover. Loving the android app Shooter to calculate dope; what a game changer. Save 8oz to 1 pound on a rangefinder.
-Cache or set camp whenever you can. I almost always set up a cache w/ my cooking and sleeping kit and hunt from that base. Save your legs for chasing and packing out critters.
-Practice, practice, practice, practice some more. Mike Clelland’s advice to practice UL techniques close to home and in relative safety is so true. Practice so you know your kit, know what to expect, can carry that 80 or 100lbs+, and can deal when, as Aron Snyder says, the s**t hits the fan. With a pack well under 35 pounds.
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