after my heart attack my feet get real cold so will they keep my feet warm while still hunting for several hours and do I need the next size up from what I wear?
there warm enough and the size is roomy if you want to add a foot warmer.
We bought two pairs, and have not yet worn them. However, we are going to Alaska soon, and at Chena Hot Springs Resort THEY SPECIFICALLY recommended this brand to deal with -40 temperatures, and to keep from losing any toes. They considered them serious, very effective boots for the situation. They recommended using them in conjunction with smartwool socks. Should you go that route, combining the socks with the boots, my guess is that you will be perfectly warm. If not, always consider dropping some 10 or 18 hour warmers into the boots, between the liner and the outside of the boot. These were the BEST that we could get, and we think they will do well.
I'm a true 9 and with the thinsulate bootie, these size 9M boots fit nice and snug, but not tight. They keep my feet nice and warm.
However, if you feel that you will need to put an additional layer of thick socks on, then I would suggest going up a size or maybe adding a sole insert between the boot and the bootie for extra insulation against the ground temperature.
I feel that there is plenty of insulation from the bootie on the top of the foot to keep warm from the air temp. Hope that helps!