Say a guy wasn't on a fly in type trip like he's talking, would most of you have a base camp set up where you parked the vehicle, or would you still try to rent horses and get your base camp in a ways??? I suppose it depends on what you're hunting and where, and how far you'll wander from the vehicle?
For a 10 day backpacking trip in September or October I would definitely go with a 4,000 to 5,000 cubic inch pack. However, if I'm only 6 to 7 miles from my truck I do 3 to 4 day trips and take time to replenish my supplies. 6 or 7 miles away is only about a half a day's trip or so for me when I'm only packing a 30 to maybe 40 pound load. 3 to 4 day trips allow me to get away with using my Osprey Exos 58 (very similar to the Sacrifice). Its just over 3,000 cubic inches and weighs about 2.5 lbs as compared to my heavy hauler the Eberlestock J107M Dragonfly. The Dragonfly is very comfortable for packing those heavy loads, but it weighs 8.5 lbs making it a 6 lbs difference.
Choosing to take 3 to 4 day trips and making a quick trip back to the truck for more food works best for my hunting area this year. 10+ miles deep into the backcountry would change my approach on packing a heavier pack loaded with 10 days worth of food. After some time in the backcountry you will soon realize what works best for you depending on the circumstances. Hope that helps.
10 days is a long time off your back espescially if you don't have a lot of backcountry experience. You are looking at 10 to 15 pounds in just food alone. I would look Atleast at a 6000 CI pack. You will need alot of stuff for 10 days.
Stash an action packer or big dry sack at or near your air-strip. At least you have a safety net, and if you tag out early, you have a nice comfortable camp waiting for you until you fly out. You can have some more "luxury" items at the strip, and most other fly-in hunters are pretty trustworthy, and won't raid your stash. We see a lot of base camps at the air-strips, with either wall tents or Cabelas style Alaknak tents serving as R and R stations for hunting parties. You can always have a spike camp between your deep camps and the strip as well. You have that luxury of time it sounds like. All of the other hunters on this post are right though, if you have never had a hard 10 day straight backpack, even with fair weather throughout; best wishes. This can be tough, especially if you are hunting sheep. The early season in 27 has the sheep up pretty high, and scattered. That late tag is much different, with rutting action and sheep down much lower. I completely agree with the other guys on this one though, 10 days is A LOT; gear and food, and hopefully a nice ram on your back can bring a skilled backpack hunter to his knees. Don't forget your wolf tags. Oh, and I agree with the fellas on a pack size as well. 6000, with the best ultralight gear you can afford to jam into it.
Your question about determining what size pack you need is an excellent one, and one that many don't think to ask. Unfortunately, many folks will recommend one size or another, normally based on THEIR gear and how much space it takes up, which isn't relevant to you and your gear/loadout.
The best way to answer your question is to lay out all of the gear you will be taking and see how many cubic inches it takes up. Then see how much space a couple days worth of food will take up. Your water you should be prepared to get whereever you are with a filter or chemical purification so you don't need to worry about ten days of water, just one days worth in terms of space/cubic inches. So, the pack size you will need is going to equal the volume of your gear, plus the volume of your food/stove fuel for however many days you will be away. This will likely be at least 6000 cubic inches unless you have very light/compact gear. Let the math decide for you then get the pack that will fit all of your stuff. More on pack fitting in a minute.
As far as your question about how the meat will affect pack size, once the animal is down and butchered most people will carry out a first load of meat and their gear, then come back with just their survival gear for the subsequent loads. Your pack should be big enough to carry close to your body a quarter/leg of whatever you are hunting. Since you are going for sheep it should be able to hold most if not all of it boned out. You can strap or pack your gear in outside pockets or in a bag on the outside of your pack, with the main bag being used to carry the meat and holding it close to your body for an easier carry and better balance.
Since you are new to backpacking or backpack hunting you should read up on how to pick a pack and/or frame that will fit your body properly. Most horror stories about packouts have to do with poorly fitting packs that hurt like hell with 50-100 pounds of dead animal in them on the walk out. The main thing to think about is getting a pack with 1) a good waist belt that will support most of the weight that is in the bag, and 2) load lifters to lift the shoulder straps off of your shoulders so that they shoulder straps are really only used to keep the pack snug against your back. To do this the point where your load lifters attach to your pack frame needs to be above your shoulders.
Hope this helps,
Thanks for all the great information guys.
How do you keep the bears and other animals out of stuff you stash?
Larry, good point on laying everything out. I've thought about it, but wasn't sure if I would come up with an accurate measurement. What are the load lifters? That is a new term to me.
Mine is 4500
Load lifters are straps that run from the front of your shoulder straps to the top of your pack frame (external frame) or to the top of your pack (internal frame). Their purpose is to lift the shoulder straps up off of your shoulders a little bit so that the weigth is not pushing down onto them rather it is pushing into your chest/shoulders from the front. With all or most of the pack's weight resting on your hips (with the waistbelt), the purpose of the shoulder straps is now just the keep the pack from flopping off of your back and hold it in place so it doesn't move back and forth as you walk. The sternum strap helps with this side to side movement too. The waist belt should be set so that it rests on the top of your hip bone; it should go across your belly button, most people wear it too low on their hips and it doesn't work as well.
Here is a picture of the load lifters actually doing what they are supposed to do. Some folks use them to pull the top of the pack closer to the back of their head to help move their center of balance in line with their bodies midline, and this can be a good thing, but the first thing you should do is to get the shoulder straps up off of your shoulders.
As for how to determine the cubic inches of your gear, just lay it out in a rectangular cube and measure L x W x H.
Hope this helps,