Neither. Each performs as it should within its limitations.
You will have to state your intended use.
There is no "one" better anything- including rifle calibers. The .300 Win Mag can fire a heavier bullet a longer distance, but is generally a heavier rifle, has more recoil, and you can carry less ammunition.
1960
Yes
100-400
It is a more powerful cartridge. The .300 Win Mag tops out at about 4000 ft lbs of energy, vs the .308 at 2800 ft lbs
To find the number that, when multiplied by 7, equals 308, you would divide 308 by 7. The result is 44, so 44 times 7 equals 308. This can be verified by multiplying 44 by 7 to get 308.
lcm(7, 4, 11) = 308.
7 can go into 308 a total of 44 times.
The cartridge in question is the .300 Winchester Magnum, and not the .308 WinMag. The .308 cartridge is about 16mm shorter than the .300 Winchester Magnum casing. The two are NOTinterchangeable.
44
Get it to a gunsmith now.