Question about grain bags

I am doing the partial mash technique that Chris Colby wrote about in by and on beer and wine journal.com.  does anyone know what the max weight a large muslin bag can hold. 
And does anyone have an ideas for possible bigger bags that will fit in a 2 gallon beverage cooler

How about 9"W*21"L coarse mesh bags. That will fit just fine in a 2 gal cylindrical cooler. Or in other dimensions…

Depends on whether you want disposable or reusable.

I will have to look for them. I also thought of paint strainer bags

For steeping a 5 gallon paint strainer bag can hold about 8-10 lbs of grist if you really push it. Can’t imagine you would need that much. Lowes sells them in a 2 count for about $6. I use them for indoor BIAB and as large hop bags on my bigger system. They rinse out easily and you can reuse many times.

I can’t go much more than 5 or so pounds in my little cooler. But the large muslin bags are starting to max out at 4

As long as your cooler has a drain I’d do a braid instead. Easier to clean…