What to look for - Sleeping Bags for Camping
Having decided on the fundamentals (ie the level of protection you need), you should then check the following:
Shape/Size:
Mummy sleeping bags are the best for heat retention but can feel claustrophobic. Get inside one before you decide on this shape.
Select a sleeping bag that gives enough space to stretch comfortably - but don't go for anything that's much bigger.
Check that your feet are nice and comfortable in the sleeping bag and that there is enough room for the extras (hot water bottle, boots) if you're likely to need them.
Check that the hood is comfortable when closed - and that there's still room for a hat if the temperature really plummets.
Check that there is a shoulder baffle/collar and that this has enough bulk to fill the area between your neck and shoulders without being too overwhelming.
Fill:
Shake the sleeping bag to check on how well the fill stays in position. If it moves around, you'll end up feeling the cold.
Zip:
Look out for a two-way zip that opens all round as this gives more options for ventilation. Check that this runs smoothly without catching on the fabric. Make sure that there is a flap over the zip (aka a baffle) and that this doesn't interfere with the running of the zip.
The zip baffle should only be attached to the lining and not sewn through the fill as well. If you plan on joining two sleeping bags together, make sure the zips are compatible.
Overall Finish:
Check that the stitching on the seams is close and tight. Tug the seams evenly to make sure they don't come apart. Open the sleeping bag and look inside to gauge the overall quality of finish.
Packing:
If you plan on backpacking when space is at a premium, check that the sleeping bag comes with a 4-way compression sack as well as the stuff sack.
Warranty:
Is there one? If so what's covered and for how long?