REI Co-op - Magma 15

A 15 degree bag will keep you warm at 25 degrees. You'll want an additional quilt or a lighter bag for the coldest nights. If you need to backpack it in, down is worth it. I have an REI 15 degree down bag. I bring a 30 degree down bag as a blanket when it gets to the low 20's. I have a -20F down bag, but it takes up too much space if I don't really need it. If you're close to your car, synthetic bags are much cheaper.

Were you camping at the lunch counter? In my experience, Kelty’s ratings are quite optimistic, I’m not surprised that you were cold. Especially considering that you were sleeping on snow, and a high windchill (I’m making the assumption that you were at the lunch counter). You don’t mention what your 35 degree bag is, but I wouldn’t be surprised if they were similar in loft/warmth. Is the PNW your usual stomping grounds? What I have for my sleeping quiver around here is: - REI Magma 17 (17 comfort, 3 limit) - EE Burrow 30 - MLD vision quilt. I think a more economical way to extend your sleep system around here, while “future proofing” your sleep system would be to buy a ~50 degree synthetic quilt like the MLD vision quilt. You can layer this on top of your 35 degree bag to boost the warmth, and to reduce loss of loft in cold conditions due to condensation. I used this during a Mt. Baker attempt earlier this year combined with my 30 degree quilt and was quite toasty warm. Had to bail on the summit attempt due to foul weather and whiteout conditions, but I was super warm at camp! You can also use the quilt alone in the summer. Then, in the future you can save up a little bit more to get the ultralight down bag of your dreams, and can still use the quilt for exceptionally cold conditions as an additional layer. It would also cost less than any of the above options.

I have Feathered Friends Hummingbird for my 20 degree bag, and a Cedar Ridge Outdoors 10 degree quilt which has the same full zip hoodless design of the Zpacks. Unfortunately Cedar Ridge went out of business. The REI Magma 15 is a nice bag when on sale. They had them for under $200 a few months back before they released the new "non-gendered" model.

Something to keep in mind is the comfort rating vs “lower limit) rating (are we all confused yet?! 😂). For that bag it’s 30f (comfort) and 20f (lower limit). I personally run cold and have a down sleeping bag (REI Magma) that’s comfort rating is 21f and lower limit is 9f and find it perfect WITH layers AND a hearty meal before turning in for the night. Overkill in the summer but for me it’s perfect. Do you know if you sleep cold or warm? What is your budget? Otherwise enjoy Yosemite. It is absolutely beautiful.

That is a dope sleep is pad. I don’t know if I am any help 😂 I’m a big fan of the REI Magma 15 since it’s all I have used and it hasn’t done me dirty BUT it is hella expensive. Which Big Agnes were you looking at? The one that looks like it attaches to your pad?

I'm 5'6" and sleep cold! Here's my set-up: - Thermarest Neoair Nxt (4.5 r value) - Rei Magma 15 in the regular size (not a lot of extra space) - Sea to Summit sleeping bag liner (reactor extreme) - Thrifted cashmere sleep shirt - Dedicated sleep pants - Dedicated sleep socks - Beanie and buff to cover my face - Occasionally I'll throw on my puffy and fleece if I get cold or add them to my sleeping bag for added warmth - 1-2 hot hands added to my bag as needed. My whole set-up probably weighs 6ish lbs, but I always bring it. I can comfortably drop down to the low 20s with this and I can easily turn layers into a pillow/treat my sleeping bag as a quilt if it's warmer outside. I'd rather be warm and carry more weight than drop weight and suffer. I highly, highly recommend a liner and dry clothes.

Three seasons where exactly? A better question may be will your trips ever have nights below freezing? You did say "at least..." so I imagine yes? If so, I'd look at the REI Magma 15. If not, try the Magma 30, or Magma quilt. There are plenty more options from really good companies, but since this is a REI subreddit, I thought I'd mention them. Make sure you have a good, warm sleeping pad. And I'm a fan of liners. Keeps the bag clean, and add some warmth too.

Just switched to[ ](https://wisechoicetoday.blogspot.com/2025/05/rei-magma-15-sleeping-bag.html)[this sleeping bag](https://wisechoicetoday.blogspot.com/2025/05/rei-magma-15-sleeping-bag.html). Light, packs down tiny, and still kept me warm below freezing.

With backpacking, many folks including myself prefer quilts. Especially with down so that they weigh and pack down to almost nothing. So this is worth looking into if you choose to. That being said, things to look for when buying a sleeping bag are comfort rating, material(down/synthetic), any specific features and build quality. Example: You can get a synthetic Walmart 10* Ozarks sleeping bag that's comfort rated for 10* for 40 bucks or REI Magma 15 which is actually comfort rated for 21* for 430 bucks. Both these bags are ISO rated for their comfort rating. Both of them will work in temperatures down to freezing and keep you alive and comfortable. Then what's the difference? Walmart bag is bulky and heavy. REI is down, so it's much lighter(half the weight), better features; like no snag zippers, pockets, draft collar etc. So it comes down what features you want, do you have a target weight for your backpacking gear and what your budget is... Last but not least, how cold is it going to get where you are looking to camp. Here are a few more bags to consider: https://www.nemoequipment.com/collections/mens-ultralight-sleeping-bags/products/coda-genderless-endless-promise-down-sleeping-bag https://zpacks.com/products/classic-sleeping-bag?aff=66 Some of these bags might be out of your budget but stuff like REI and nemo go on sale multiple times a year. You missed a pretty big one in Nov.

If you want light weight, small packed size and good temp rating… the magma by REI is the best bang for the buck… because of the size choices. If that is to much… The Trailmade is super inexpensive, and comes in a variety of lengths and widths. It is not as light, nor as compactable. If you were in the store, I would ask a whole bunch of questions… side, back or stomach sleeper? Do you roll? Where do you normally get cold? What is the likelihood of the bag getting wet? Etc… etc… I’d ask because there are so many options and each kind of sleeper works with a different kind of bag. But if you want the lightest and most compact… and best bang for the buck… the magma is the way to go? also do not forget to buy or make a liner. No sleeping back should be used without one!

Remember that you can move your legs around all you like by moving the sleeping bag with them. I sleep in the fetal position in a very narrow bag because I curl the bag into that position with me. (I have REI's magma and it's extremely toasty)

Try a quilt. I recommend the sierra designs 20(?) or rei magma

I have also gone to ground. I took my quilt with me and love it. I have used a sleeping bag, and it just isn’t as nice. My quilt is the Warbonnet Diamondback, and my sleeping bag is the REI Magma. I have never had cold sleeping problems, I just enjoy the quilt more.

I went with the Magma and a Nemo Tensor wide sleeping pad. Thanks for the recommendation

The REI Magma mens/women's bags zip together and are wonderful. They have both 15⁰ and 30⁰ bags.

My order of preference, without prying more info out of you would be: 1. Magma 2. Radiant 3. Nemo … anyone giving you numbers after the name of the bag is guessing because you never mentioned what temperature rating you need and what geography we are talking about. In terms of r-rating we would need to know what mattress pad you are shlepping too…