The above picture shows a pair of USGI N1-B mukluks in new, unused condition. I’ve been using this type of dry cold foot wear since 1981, when I was assigned to a base in upstate New York. We didn’t use them straight, ‘out of the box’, though. We used a ‘Kaizen’ approach, even though we didn’t know what the term was or meant at the time. The guys just knew we needed to make them better because our particular section was outside one hell of a lot in deep, dry cold, and warm feet was a primary objective, in fact, having warm feet and hands added many hours to operational capability. There is a proportionate relationship to how long one can operate in extreme cold to how warm one’s hands and feet remain while doing so.
These things come with a wool booty, which is pictured below, and which we immediately discarded.
We’d go beg, borrow, scrounge, trade, or, if we had to, buy a pair of pac boot felt liners and another felt insole pad.
Last thing we’d do is go get a couple of cans of ‘Scotch Guard’, which at the time, was the only waterproofing substance we could find on the civilian market for canvas. Today, I use ‘Camp Dry’, but there are other brands, so whatever your favorite one is will suffice nicely.
Once we had all the components together, we’d do a test fit. Put the additional felt insole into the muk, then put the boot liner in. The fit should be such that it completely fills out the mukluk, and when you put it on (I’ve only had to wear one pair of winter socks with this set up…ever), it should fit snugly, but not uncomfortably snug. I wear a 9 wide shoe; I use a size Medium mukluk, and with the above parts in it, my foot is comfortably snug inside the muk when I’ve got it laced up (which should be done very snugly).
If the test wasn’t successful, as in there was too much room, and yet another insole, or if it was too tight, remove an insole. The muks come with one thin one; 2 of them make a huge difference in how much insulation you have in the rubber bottom and side sole. Your boot liners should be thick enough to take up for the insole if you have to remove one. The other thing that could be done if you wanted to keep the 2nd or 3rd insole is to move up a size in your muk, but remember, these things run huge and your mileage will definitely vary.
If the test was successful, meaning that fit and feel were good, we’d strip out the muk and take our water proofing agent and use an entire can (remember, back then it was ‘Scotch Guard’) on one mukluk. Overkill? Sure it was. Better too much than not enough. Especially if the weather could change from dry to wet cold. Same consideration for any northern tier AO with a blend of dry and wet cold. Today, with ‘Camp Dry’, I use about a 1/4 can on each boot, concentrating on the top of the ankle down and the toe, with a complete covering of the rest of the muk. It’s still wet, just not dripping like we used to do it. (‘Old Schooler Tip’: Those of you who wear M-65 (old school field jackets) jackets, you can do the same thing to them and increase their water resistance. Concentrate on the shoulders, top chest, top back, and sleeves, with complete coverage of the rest of the jacket. I’ve been in the rain for hours with a treated field jacket and was completely dry inside. Just sayin’….)
After the muks cure (about a week), meaning you can’t smell the ‘Camp Dry’ or other waterproofing agent anymore, assemble the mukluks and you’re good to go. If you’re out doing an overnight in the winter, and you’re getting in your bag, make sure you either drive some sticks into the ground/snow (if possible) and turn your muks upside down on them, or at least, inside your lean to (you should not be using a tent if you’re practicing NPT winter operations) upside down. Doing so keeps any moisture (snow, frost, frozen condensation, whatever) from settling into the felt. In extreme conditions, you can remove your felt liners and put them in the bag with you over night next to your body. They’ll be nice and warm in the morning.
Note on the above: Assumes you are not in a ‘potential danger’ situation and can take off your boots while you sleep.