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  • Big Agnes - Lost Ranger Sleeping Bag: 15 Degree Down - Blue Stripe

Big Agnes Lost Ranger Sleeping Bag: 15 Degree Down

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    18 Reviews


    Get lost. Stay warm. Stay protected.

    The Big Agnes Lost Ranger 15 Sleeping Bag blends backpacker-friendly weight with bad weather camping protection. DownTek treats the lofty down insulation with water-resistant protection to retain its loft and warmth in rainy weather and moisture-riddled environments. Insotect Flow Construction optimizes insulation by strategically placing vertical chambers with Flow Gates to minimize shifting and to ensure warmth where you need it most.

    Big Agnes also equipped the Lost Ranger with a water-resistant shell and a downproof lining for extra protection and comfort. The lining has loops to attach separate liners, and draft tubes cover the hood, collar, and full-length zipper to keep brisk breezes at bay. For a roomy rectangular-shaped bag, the Lost Ranger is surprisingly light and compressible to take backpacking. Since Big Agnes doesn't insulate the bottom of bags, be sure to pair this sleeping bag with a 20in sleeping pad.

    • 15F temperature rating
    • DownTek water-repellent down insulation
    • Insotect Flow Construction
    • Rectangular shape
    • Water-resistant shell
    • Downproof lining
    • Draft tube around hood and collar
    • Full-length zipper
    • Pad sleeve and pillow pocket
    • Internal fabric loops
    • To reduce weight, Big Agnes sleeping bags have no insulation at bottom
    • Item #BAG002W

    Tech Specs

    [shell] nylon ripstop, water-resistant coating, [lining] nylon microfiber, stain-resistant finish
    650-fill DownTek water repellent down
    Max User Height
    [regular] 5 ft 10 in, [long] 6 ft 6 in
    Shoulder Circumference
    [regular] 70 in, [long] 73 in
    Hip Circumference
    [regular] 66 in, [long] 69 in
    Foot Circumference
    [regular] 54 in, [long] 55 in
    Draft Tube
    yes, collar and zipper
    Pad Retainer
    yes, 20-in rectangular pad
    Fill Weight
    [regular] 14.5 oz, [long] 17.5 oz
    15 F
    Storage Sack
    Stuff Sack
    Stuff Size
    [stuff sack] (regular) 8 x 17.5 in, (long) 8 x 17.5 in, [compressed bag] (regular) 8 x 7.5 in, (long) 8 x 8.5 in
    Claimed Weight
    [regular] 2 lb 11 oz, [long] 3 lb 1 oz
    Recommended Use
    camping, backpacking
    Manufacturer Warranty

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Perfect for side sleepers

    • Familiarity: I've used it once or twice and have initial impressions

    I've never loved mummy bags because as a side sleeper if I turned in the bag my knees wouldn't fit, if I tried just rolling the entire bag it seemed that I was always falling off of the sleeping pad or fighting with the bag. This bag eliminates both of those problems. The built in pad holder is genius. I used a Klymit Static V and it fit and worked perfectly. I could roll over in the bag and be perfectly comfortable. I'm 5'10" and the regular length bag is perfect.

    The bag includes a storage bag and a smaller stuff sack but not a true "compression" sack. I put my pad and the sleeping bag into the stuff sack to force a bit more compression and save some room.

    I recently used the bag for 4 nights in Nepal. Temps were in the high 30s to low 40s at night so I wasn't pushing the temp rating but I was almost too warm at night. The bag has a reversible zipper so I unzipped a bit near my feet to allow for a bit more airflow and was very comfortable sleeping barefoot wearing nothing but underwear. I suspect that as I push closer to the 15 degree rating I'll need long underwear and an insulated pad. I'll be winter camping in a couple weeks so I'll try to report back.

    The materials all feel very high end. I like the design with minimal insulation on the bottom so that there is more on the sides and top at the same fill weight. There's nothing "gimmicky" about the bag, no extra pockets on the inside or anything like that, just a simple draft collar and drawstring. There's very minimal velcro in the fastening system at the neck which I consider a positive feature.

    Perfect for side sleepers

    Prepare to be cold...

    • Familiarity: I've put it through the wringer

    ...if you trust the 15 degree rating. I've used this bag for a couple years in multiple camping situations and have never found it to be warm enough below 30-degree nights. I now use it as a 'guest' bag for the couch inside my house, or as a liner inside another bag. I am a woman, and suspect that most who are happy with the warmth are men. I would rate this bag at 30 degrees unless you're sleeping in a down jacket with leggings.
    Warmth aside, I do love that there is more room to move inside this bag. The sleeve for a pad is nice, although I prefer to sleep atop an XL insulated pad. The zipper invariably gets stuck.
    All in all a decent bag, especially if you can get it on sale.

    The EN temperature ratings are one of the few things where I find gender-specific products matter. Women's sleeping bags typically go by the EN 'comfort' rating, which is 15-20 degrees warmer than the EN lower limit rating for men's bags. So a 15 degree men's bag would subjectively be similar to a 30 degree women's bag.

    Karen is right--and I'm a man! The bag is not warm below 20 or even 25 for anyone unless wearing full clothes and a jacket--probably due to the extra air space from such a large bag. See my December 2015 review when I tested this in different ways at 9, 15, and 25 degrees. But do NOT think that you will be warm at 15 without a puffy jacket, wool socks, and full pants.

    Haven't used this yet but...

    • Familiarity: I've used it once or twice and have initial impressions

    I have a few friends who recommended this bag to me. They all love it for its durability, warmth, and easy of packing. Sorry to get anyone's hopes up, I haven't tried it yet but am super stoked to take it down to Moab this weekend to give it a go!

    The Ranger always keeps you comfortable

    • Familiarity: I've put it through the wringer

    Looking for a warm bag with the latest technology to keep you dry and warm? Look no further, the downtek (water resistant down) vertically insulated baffles keep the warmth in and help you maintain a lofty dry bag that can maintain quality use for years to come. The custom pad retainer allows your big agnes pad to slide and lock into place so you never slide off your pad onto the cold ground in the middle of the night. If you have additional questions please feel free to reach out at - or 801-204-4533.

    Warm and comfortable sleeping bag

    • Familiarity: I've used it several times

    I purchased this sleeping bag for my wife to use during our recent backcountry camping trip in Yellowstone National Park. The nights dipped down into the 30 degree range but she said she was not cold at all and very comfortable. Love the integrated sleeve for the sleeping pad!

    Great Sleeping Bag

    • Familiarity: I've put it through the wringer

    Just finished a week in the Montana back country. Temps got down in 20's. The 15 degree bag did well. I wore my coat a couple nights, but that did the job well. I'm 6' 0" and had the long/wide bag so I could sink into it. I recommend the bag with the SL pad, it was great too.

    Lost Ranger

    • Familiarity: I've used it once or twice and have initial impressions

    This bag is just what I was looking for. I have never tried the type of bag where your pad fits inside, this works well for me. I am a side sleeper and this bag has enough room for me to do that without feeling trapped. The only drawback is when laying on my back my arms get cold if by my side. The bag has very little insulation on the bottom, the pad is your insulation, but the pad is not as wide as the non insulated part. Overall it is a great bag and has a lot of room to move around.

    Great Sleeping Bag

    • Familiarity: I've used it once or twice and have initial impressions

    I bought this bag and my wife the Roxanne. Awesome bags. I am a side sleeper and for the first time was able to sleep and roll over no problem. Looking forward to using this bag for a week in Yosemite in two weeks!

    Very happy with this sleeping bag

    • Familiarity: I've used it once or twice and have initial impressions

    I've recently bought this sleeping bag and have used it twice so far. I'm 6'0" and this was a great fit. It definitely kept me warm, which is saying a lot since I am almost always cold. Loved the extra room available in this mummy-style bag. I sleep on my side so I was able to turn inside the sleeping bag without have to worry about my position on the pad.

    Speaking of the pad - the pocket available to slide the sleeping pad inside is genius! I didn't have to worry about slipping off of it at all.

    Definitely a great buy! Can't wait to use it again.

    Great Bag

    • Familiarity: I've used it several times

    So far love the bag. This is first BA sleeping bag I have had, and thus, the first experience with the integrated pad sleeve. If you do allot of backpacking, and haven't tried the BA system, do yourself a favor and check it out. Love it. So the bag itself is great, really warm, in fact unless its but puckering cold it's probably to warm for many campers. Also, make sure if you use it in weather that cold use an insulated pad. The fill from the bottom has been moved to the top which gives it a very nice heft and feel, cozy you might say. All in all very happy with the construction, and performance through a couple of uses and man do I love that sleeve, did I say that already?

    Love it

    • Familiarity: I've put it through the wringer

    PleNty toasty. Used it down to 20 degrees with a silk liner and was actually a little too warm. Like the slot for the air pad quite a bit. I got the tall because I like a little room to move and toss and turn most nights. Compresses down well.

    Get an insulated pad for cold nights!

    • Familiarity: I've used it once or twice and have initial impressions

    Chucked my old sleeping bag in favor of this Big Agnes Sleep System bag b/c I was tired of sliding around on pads in the night. Works beautifully, well constructed, there are a few bare spots however. I let it sit out for 24-hours and it mostly filled in the spots.

    Used recently on a weekend hike, 24 degrees out the first night and I was a bit chilly and could feel the cold air coming in from below. I had a BA Air Core non-insulated pad that was not keeping the cold air out, I knew it was a gamble taking it and not getting an insulated one but funds are tight and the Air Core was a gift. I got 1/8th inch closed cell foam pad I'm gonna shove btw the mattress next time to keep the cool air out.

    @ 30 degrees the bag and Air Core kept me plenty warm with only sports skivvies.

    I'm a side sleeper so I was really happy to see how big this bag is and love how I can move around in it vs. my old tight fitting mummy. Flopping around all night no longer wakes me up when I fall off a pad or can't move my legs freely. If you are a bit skinnier like I am though 6'2" 170lbs keeping heat in such a big bag is a concern but a compromise I feel is worth the extra comfort.

    Sweet bag!

    • Familiarity: I've used it once or twice and have initial impressions

    I haven't been able to use this bag yet. But i just wanted to comment on the construction of this bag. Its built to last! i know i'll have no problem staying warm when going on my backpacking trip this this summer.

    Great Bag but Exaggerated Temp Rating

    • Familiarity: I've used it several times

    I have two bags rated much colder than this one (Marmot Trestles Zero degree bag and a minus 20 degree down bag), but for comfort and design this is the greatest bag I have owned in over 30 years of winter camping! I love the super roomy width and the brilliant integrated pad system. (My -20 bag traps me like a mummy and can slide off its pad.) For the price and temperature rating, which I have tested at 25, 15, and 9 degrees, this is one of the best value bags around--BUT ONLY IF you wear a puffy jacket or otherwise fill the extra dead space created by such a roomy bag (this is simply a trade-off one must accept and deal with it).

    So if you do this, then I'd rate the bag as comfortable at 15 degrees, but otherwise no lower than 25 degrees. And in any case you MUST have a serious pad beneath you (which I would define as any pad costing around one hundred dollars / non-sale price).

    Finally, because I wanted a non-mummy-bag zero-degree option, I put a cheap, thin 41-degree Kelty Cosmic down bag INSIDE the roomy Lost Ranger and slept warmly at nine degrees with no tent or jacket. On another 8-degree night, I inserted an older model 30-degree lightweight Marmot Never Winter bag and only wore cotton pajama pants and a long-sleeve cotton polo shirt...I was so warm that I had to take off my socks and sleep barefoot! To save further typing, I will just say that I agree with everything else that John V. says below.

    Nearly perfect backpacking sleeping bag

    • Familiarity: I've used it several times

    I got the Lost Ranger 15 because I wanted something WARM that didn't weigh a ton or cost an arm and a leg. The sale price offered by was unbeatable, so I took the plunge. Big Agnes has hit on a very smart concept with their bags. Eliminating the insulation on the under side and relying on a good sleeping pad for that area where you just smash the down flat anyway saves a bunch of weight AND bulk, which makes this bag easy to stuff and highly compressible--saving lots of room in the backpack. This design has also allowed them to fill the upper part of the bag generously with the down where you really need the insulation in the first place. It also allows them to cut the bag much more generously than what you typically feel in a traditional "cold weather" mummy type bag. I LOVE the extra roominess in this bag. It's still a mummy shape, but it's not at all constricting like most others I've tried, and allows me to easily roll over and change positions, and I never feel like I'm wrapping the mummy webbing more tightly around me like I do in other bags. It's glorious NOT feeling like I have to sleep in the funeral position on my back only. It's hard enough to get a good night's sleep in the backcountry without fighting your bag for it. There's no fight with the Lost Ranger--it really does feel different and roomier, yet not loose and warmth challenged. The added bonus of the non-insulated underside is the built in sleeping pad sleeve that works like a charm with any 20" wide pad. I teamed my Lost Ranger with the Nemo brand Cosmo Air 20 pad (72" long) and it mates perfectly inside the sleeve. The built in openings at the corners of the sleeve are perfect for the inflation and deflation valves as well. With my pad securely held inside the sleeve, I NEVER have to worry about rolling off my pad, and when I move around and change positions as indicated above, the pad stays right where it's supposed to--directly underneath me. I am VERY, very happy with this purchase and the way it all works together for comfort as well as light weight. I haven't had the bag out in extremely cold weather yet--nothing below 30 degrees, but I'm confident it will perform as advertised. It just has that feel to it and fluffs up very nicely. I highly recommend this bag to anyone looking for a good deal on a colder weather bag with premium materials and design. Big Agnes knocked it out of the park with this one. And thanks Backcountry .com for beating everyone's price!! And for getting it to me in only two days for no extra charge. Great purchase experience.

    So far so good...

    • Familiarity: I've used it once or twice and have initial impressions

    I purchased the lost ranger along with a sea to summit silk liner, the thermarest base camp sleeping pad, and the thermarest luxury lite mesh cot. I tried the combination in the house overnight and it was very nice. I took it car camping in rainy cool weather.. It got down a little below freezing and all was well. With a pillow in the sleeve under the bag it works perfectly... This combination of bag pad and cot is amazing... I will never go back on the ground. This is the best sleeping bag I have ever owned.

    I plan on going camping again in a couple of weeks. The evening should bring lows in the twenties and possibly teens. I will have a better idea then of how well it holds in the heat. I am a hot sleeper desire to spend time outdoors has now been tapped again thanks to the comfort level I have achieved with this new combination... Whew!

    Good bag

    • Familiarity: I've used it several times

    Buy it and you will be happy..... wish it weighed 1/2 as much and cost 1/2 as much.... but if you are like me and a little harder on UL gear... then you know the value of quality.... this is a good bag and I sleep pretty good in it. 5'10" - 227# ...and am wide in the shoulders/hips....
    Extra thoughts.... I will say this is too warm a bag for me in the summer with an insulated pad..... go without an insulated pad in 40F+ or pack a Woobie instead.

    Embrace It....

      Ok, so let's get to it...I have always HATED the traditional mummy bag and (insert favorite pad here) combo. Endless nights pent sliding off your pad, kicking your feet around for room that's just not there, you know, all the stuff that us "mobile" sleepers hate. On the flip side, have never wanted to deal with the weight of rectangular bags or other pseudo car camping setups. Problem now solved. Enough room to flail around, but not so much that it feels chilly, integrated pad sleeve means that you may indeed slide, but not off the pad. And for some reason, when you integrate the pad to bag like this it just feels cozier. Weight is decent, especially when paired to the new and very awesome Therm-a-rest Evolite pad. Look, to the many that I know feel the same way...stop fighting it. A good nights sleep in the BC is worth a little extra weight, and to your purist friends who may deride you? Let them test lay in it and they may never give it back....

      Unanswered Question

      If I wanted to get an over-bag for the lost ranger in order to add a few degrees to it for winter camping - what size would it have to be? Would I need to go for a Long or would regular do?
      I was considering the cross mountain bag, which would add another 20 degrees they suggest.

      What pad sizes work with this sleeping bag?

      Pad sizes that work with each sleeping bag size:

      Regular (Sleeping Bag): 20"x72" or 51cm x 183cm

      Long (Sleeping Bag): 20"x78" or 51cm x 198cm

      Anytime you have a Big Agnes question, shoot me an email and I'll make sure to work with you 1-on-1!

      Jared D.

      Expert Gearhead