Mountain Hardwear
Mountain Hardwear Bishop Pass 15
No citable owner-review average published for this one, so no stars.
A lot of down for the money: the Bishop Pass carries more fill than almost any bag at its price, at 650 fill power, and publishes an ISO comfort rating of 26 °F. Five and a half inches of measured loft in a 20-denier shell, with an expanded shoulder, hip and leg cut that Mountain Hardwear calls Performance Plus and most people would just call comfortable. At 37.4 ounces it is heavy for a 15-degree bag, and all of that weight is the low fill power buying loft through bulk.
Label against lab
Sold as a 15 °F bag; its ISO 23537 comfort rating is 26 °F, which is 11 °F warmer than the name suggests. Plan around the comfort figure, not the label. Why the gap exists
At that temperature the pairing table wants at least an R 4 pad underneath it.
Specifications
Highlights
Features
- ISO or EN rated
- RDS down
- Draft collar
- Full-length zipper
- Stash pocket
What it does well
- ISO comfort of 26 °F published, on a bag that costs $335.
- Five and a half inches of measured loft — as much as bags costing twice as much.
- The Performance Plus cut adds room at shoulder, hip and knee without going to a semi-rectangular shape.
- RDS-certified 650-fill down and a 20-denier shell that is tougher than the ultralight bags'.
What it costs you
- 37.4 ounces, and 650-fill down means it packs large for its warmth.
- The down is not hydrophobic-treated.
- Mountain Hardwear publishes the comfort figure but not the lower limit, so half the ISO picture is missing.
- Only the Regular's figures were verifiable from published sources; the size run is not tabulated here.
Those two lists are drawn from Mountain Hardwear’s published specifications and from reviews that measured them. They are not owner sentiment — anything owners said appears under its own heading below.
What owners say
Distilled from owner discussions and long-term published reviews, not from anything measured here.
Owner assessment of the Bishop Pass is unusually well calibrated, and the reason is that they read the right number. The recurring line is that a 15-degree rating means comfortable to about 35 °F — which is almost exactly the published comfort figure, and a good example of owners getting this right where marketing does not.
The praise is about value and room. On sale it lands under $200 for a bag with more down in it than most at the price, and owners describe it as roomy for a mummy, which matters more to most people than four ounces does.
What 650-fill down always costs is weight and bulk. Owners who also own premium bags keep this one for trips where neither matters.
What owners like
- Owners call it a great bag for under $200 on sale, which for a down bag with this much fill is unusual.
- It is described as roomy for a mummy, which owners raise unprompted as a reason to prefer it.
- Owners who also own bags from bigger names keep it in rotation rather than replacing it.
- Its published comfort figure gives people something concrete to plan against, which several owners do explicitly.
Common complaints
- Owners who have used it report comfort down to around 35 to 40 °F rather than to the 15 on the label — which matches the published comfort figure but not the name.
- Owners with a colder version of the same bag preferred a competing bag unless conditions were genuinely severe.
- 650-fill down means it is heavy and packs large for its warmth.
Questions owners ask
How cold can I take it?
Is it roomy?
Is it good value?
Mountain Hardwear Bishop Pass 15, head to head
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