Depends on what size pillow you are putting inside.
They have a chart listing all compatible pillows.
Otherwise your jacket etc work out rough size needed.
1. Klymit inside a Goosefeet Gear Down.
Not too heavy,warm and thickness right.
2. Also use a Sea to Summit Down which is super light and velcros onto mat.
3. Thermarest Compressible is also good but is now the wifes.
You will need to try a few and details like how they fit in the hood...
Interestingly a couple of posts on here Winchester Featherweight 30-06.
I still have one and they are not terribly weighty and shoot well.
It has all been done before.
I have a Rem 700 .243 in a carbon stock and you know what about the same weight as a Featherweight.
Old Husqvarna's are also a...
I have it post chemo ,it unfortunately only kicked in when I had finished chemo.
4 years now.
Feet really bad and hands with a combination of arthritis not too much fun.
To get a reasonable sleep tried a few drugs but didn't like them.
Have settled for the following.
Warm bed in winter...
One thing the 30-06 has going for it is the 30-06 and cartridges of similar dimensions feed really well compared to chunkier stubbier cartridges.
When you need a second shot it just works.
I have a 1980 BJ40 and still use as daily driver to work and weekends.
Have probably spent what it is now worth.
I think you have to decide to keep it.
Then do not skimp on anything you have to keep it up to scratch.
The only thing I haven't touched is diffs, gearbox and transfer case.
But I can...
Volume really becomes the issue even with the expensive and warm bags.
I have an Exped Waterbloc for here in NZ and as good as it is for what I want it it is heaps bulkier compared to EE Revelation quilt or Sea to Summit Micro 3 I use.
Put them to bed warm.
Well rugged up, food in their belly.
Make sure they are insulated from the cold, too many people put the kids on a stretcher/cot without insulation underneath them.
We used to regularly camp with our kids down to -9/10c.
They loved it.
For my wife and I we use an old original Thermarest for her and a Exped SIM for me under the 40-50 mm foam mattress.
Both do the job the Exped is a bit wider but both the same thickness.
Then whatever sleeping bag for the expected temps.
NZ might be a "tropical" South Pacific Island but any time...