I have one raw file contains system:
$file my.raw
my.raw: x86 boot sector; partition 1: ID=0×83, active, starthead 1, startsector 63, 64259937 sectors; partition 2: ID=0×5, starthead 254, startsector 64260000, 2843505 sectors
try
$mount -o loop my.raw /mnt
mount: you must specify the filesystem type
Solution:
$mount -o loop,offset=32256 my.raw /mnt
Root:
The number too big for calculations, so set offset here.