which one is better n which 300 or which 7mm

for what?.............

What are you hunting, how sensitive are you to recoil, and what do you want it to do?

Which .300?

Cant help you if you don't tell us what your hunting and your max range and how sensitive you are to recoil. But to be honest id stick with the regular .7mm Rem Mag or .300 Win Mag but thats just personal preference.

All around whitetail n elk. Recoil dont matter

300 win mag rem mag rem ultra mag h&h n savage wby mags

For whitetail? Are you serious? Why would you want a 7mm or 300 mag for whitetail?
I know dead is dead, but these generate waaaaay too much energy, recoil, cost of ammo is more and if you reload, burn excessive amounts of powder.
If you want to use a 7mm bullet for whitetails, why not use a 7-08, or a .280. Even a 7mm Mauser. In the 30 cal you have the 300 Savage, 308 Win, 30 T/C, and the everlasting 30-06.

Well if your talking long range (300-400 yards) id say a 7mm Rem Mag would be fine. But keep in mind most deer are killed at ranges under 100 yards so id look at a .270 or .30-06 something along those lines no need to use a magnum for a regular deer rifle. And with a magnum ammo cost more you ruin more meat more recoil more muzzle blast.

7MM Rem Mag. for long distance shooting on mulies.

On larger deer like Elk the .300 Win Mag will help to anchor them on longer shots.