The REI Magma 30 Sleeping Bag. Photo: Rebecca Parsons//The Inertia
If a movie were ever made about my life, there’s a good chance it would be called The Pursuit of the Perfect Sleeping Bag. Okay, maybe that’s not quite true, but I do love me a good sleeping bag and have tested my fair share in my search for the perfect one. And what is a sleeping bag? Does it even exist? For my money, I’m looking for a lightweight, warm, packable, and, of course, comfortable option. Recently, I got my hands on the REI Co-op Magma 30 Sleeping Bag ($349), and while it may not be absolutely perfect in every single way, it sure does come close. It’s warm, cozy, packs down small, and it comes in lots of size and width options, so it’s easy to find your perfect fit. Plus, while it might not be the absolute pinnacle of what a sleeping bag can be, the price is right, which matters when selecting a bag, too.
Bottom Line: The REI Magma 30 Sleeping Bag is an affordable, lightweight sleeping bag that packs down small and delivers a cozy and comfortable night’s sleep. And while it’s not a true budget bag, at $349 it offers near-premium performance at a really good price.
Check Magma 30 Price on REI Check Magma 15 Price on REI
Related: Best Backpacking Sleeping Bags | Best Backpacking Backpacks | More Backpacking Gear
The Magma 30 packs down small. Photo: Rebecca Parsons//The Inertia
Putting the REI Co-op Magma 30 to the Test
I run cold at night, so I typically opt to use sleeping bags that have a significantly lower temperature rating than the conditions I’m actually in. But I’ve also been known to complain that my backpacking sleeping bags are oversized, and I’ve dreamt of having a super compact bag. I split my time between Santa Cruz, California, and Oahu, Hawaii, so there’s truly no reason I should need a 0-degree or even a 15-degree bag. The Magma does come in a 15-degree option, but to truly test out if the Magma delivers on the warmth it advertises, I opted to test the REI Magma 30 Sleeping Bag.
To put the REI Magma 30 Sleeping Bag to the test, I used it during a wintertime camping trip in Big Sur. The weekend of my trip was cold and wet, perfect conditions for testing the Magma. The highs were in the 50s, and the evening low dipped into the high 30s, well within the Magma’s advertised comfort range. I’m 5’7”, 125, and tested the “medium” sleeping bag.
The Magma 30 comes in nine genderless size options. Photo: Rebecca Parsons//The Inertia
How Does the Magma Perform?
REI Co-op Magma 30 Sleeping Bag
Temperature Rating: 30 degrees
Tested Lower Limit: 24 degrees
Tested Comfort: 34 degrees
Insulation: Down
Shape: Mummy
Gender: Unisex
Weight: 1 lb. 8.4 oz. (medium)
Pros: Lightweight & packable, lots of size options, water-resistant
Cons: Draft collar is awkward when sleeping bag isn’t zipped, zipper can snag
Sizing Options
The fit of your sleeping bag is important when it comes to warmth. To ensure you stay as warm as possible, you want a snug sleeping bag, but you want to make sure you have plenty of room to stretch out. Most sleeping bags only come in a few different size options, but the REI Magma 30 Sleeping Bag offers nine genderless sizes: Short Narrow, Short, Short Wide, Medium Narrow, Medium, Medium Wide, Long Narrow, Long, and Long Wide. This helps dial in what amount of space you actually need. Best of all, they’re all the same price (some manufacturers charge more for larger sizes).
At 5’7”, 125 pounds, I opted for the medium sleeping bag. The medium says it can accommodate up to 71”, or 5’9”. I was a little nervous that just two inches to spare might not be enough, but I found that it actually fit perfectly – there was hardly any excess room, but I didn’t feel claustrophobic either.
The insulated hood is a game-changer on chilly nights. Photo: Rebecca Parsons//The Inertia
Warmth/Weather Features
Using a 30-degree bag whose comfort rating is 34 degrees when the weather was planned to dip to 39 degrees made me nervous. But I had a feeling the REI Magma 30 Sleeping Bag would deliver, so I decided to go for it, but packed an extra blanket just in case.
The Magma might be a great value, but it doesn’t short on premium warmth retention features. The sleeping bag is insulated with water-resistant 850-fill-power goose down paired with a supple recycled lining that makes for a comfortable and warm sleep setup. The bag has a contoured hood with two drawcords that allow you to cinch it tight while inside the sleeping bag. The Magma also has an insulated yoke, or as I like to call it, the neck collar, that fills in the space between your neck and shoulders. The bag is mummy shape, so it fits snug without being restrictive to trap in heat. Finally, the shell is coated with a durable water repellent finish that works to repel any dew or moisture that may bead up on your bag.
The included mesh sack is perfect for storing the Magma when you’re not using it. Photo: Rebecca Parsons//The Inertia
Packability
One of my favorite things about the Magma is how packable it is. For the medium bag, it packs down into a stuff sack measuring 7 x 15 inches. It’s easy to get in there, too, no wrestling, you just simply stuff it in and cinch it tight with the drawstring. You gain a little size with the Magma 15 but not much – it packs down to 7.8 x 16.5 inches.
The Magma 30 is also insanely light. At just 1 lb. 8.4 oz., it is one of the lightest sleeping bags I have ever used, making it a great option for backpacking. When you aren’t using the Magma, it also comes with a mesh storage bag to keep it from getting musty and avoid compressing the down so it stays loftier when you need it.
The draft collar is great when the sleeping bag is fully zipped, but a little awkward when it’s unzipped. Photo: Rebecca Parsons//The Inertia
Drawbacks
I don’t have a lot of complaints about the Magma 30, but something a little funky is the insulated yoke or draft collar. When it’s chilly, and your sleeping bag is fully zipped up, it’s so nice to have. But, when you don’t have the sleeping bag fully zipped, it’s kind of awkward — it’s an extra section of material that just kind of flaps around.
The Magma 30 boasts that it features an anti-snag zipper. The dream, right? Sleeping bag zippers are notorious for getting caught. Unfortunately, I didn’t notice a difference between the zipper on the Magma and the zippers on most sleeping bags. If you’re careful when zipping it up, it doesn’t snag, but when I wasn’t paying close attention, the material definitely caught in it.
The “anti-snag” zipper is only moderately effective. Photo: Rebecca Parsons//The Inertia
The Competition
If you’re looking for a sleeping bag that’s similar in weight but has a lower temperature rating, the Enlightened Equipment Revelation Quilt is a great option. Its warmth rating is 10 degrees, but it is a quilt, not a true sleeping bag. That being said, it doesn’t restrict movement at all and is filled with 850-fill down.
If you’re searching for something a little more budget-friendly, the Kelty Cosmic 20 is a great option. At 2 pounds 7 ounces, the Cosmic is relatively lightweight and compressible but not quite as light as some other options. The sleeping bag sports a mummy shape and has an expanded foot box, so you don’t feel claustrophobic. At $170, it’s a great deal.
The Magma 30 is a great backpacking sleeping bag. Photo: Rebecca Parsons//The Inertia
Final Thoughts
The REI Co-op Magma 30 Sleeping Bag is incredibly lightweight and packable. Weighing in at 1 lb. 8.4 oz. with a packed size of 7 x 15 inches, it’s a great option for backpacking as well as car camping. Featuring 850-fill-power goose down, a mummy shape, a contoured hood, and an insulated yoke, the Magma is a cold-weather dream. Available in multiple sizes and warmth options, it’s easy to find the perfect sleeping bag for your needs.
Check Magma 30 Price on REI Check Magma 15 Price on REI
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