RE: 300 win mag
It does have to do with a 300 mag if you are comparing it with the same bullet typeout of something likea 25-06.
Sureyou can do the same thing with other lighter cartridges if you change to heavier constructed bullets like a Barnesbut if you are comparing a 300 mag with a 180 grain ballistic tip to, say,a 25-06 with a 100 grain ballistic tip the 300 should blood shot meat less.
There are a bunch of other factors to consider but all else being equal, as a general rulea heavier and larger diameter bullet will do less meat damage than a lighter wieght and smaller diameter bullet.