.30-06 is a much more powerful round with flatter trajectory and greater impact energy.
That said, for shots on mid-sized game (like deer) at ranges out to 300 yards, it makes no difference which of those two rounds you use, only that your shot is accurate.
Both rounds are plenty powerful enough for those common hunting scenarios.
For long range shots or very large game (large bears, elk, African game, etc.)
.30-06 is a much better round.
Being a good marksman and only taking responsible shots (that you know will kill instantly with one shot) is by far the most important thing.
outdoors.stackexchange.com/users/2696/blue9
So the question remains.......what is the difference.
Well in my experience there is very little difference when we are talking about bullet weights up to 180gr.
A friend of mine has a 30-06 and I use a .308 Win.
We put our money together to purchase heads (Nosler custom competition 155gr HPBT) to reload ourselves and we noticed something very interesting.
Our first loads, we were both achieving MVs of 2550fps.
Both 26" barrels with 1:12 twists.
However my friend could not achieve good groups at those speeds.
He has had to go down to 2300fps to achieve acceptable groups.
So essentially what we have here is a .308 Win that is out performing a 30-06 LOL.
This is only because, I presume his rifle does not like that bullet when it is travelling faster than 2300fps......
but there you go.
A lot of the difference will also be dictated by the rifle being used.
outdoors.stackexchange.com/users/11144/Sebastian
I have owned, reloaded, and hunted with both 30 caliber rounds and have to say that they are both very effective and capable for almost all hunting applications.
The first comparison I can offer is felt recoil, the 30-06 is a little bit more than 308 in this area.
So For new shooters still getting use to shooting with a scoped rifle 308 will probably be the best option.
Secondly I have to mention the cost factor.
In today's market 30-06 is primarily sold for hunting purposes only, this is not the case with 308 win,there is a large variety of military surplus ammo cheep and plentiful.
This cost advantage gives you the benifits of being able to shoot more ammo, so more practice is being done at the range.
The 308 cartridge operates at a lower barrel pressure so a typical barrel 308 can last 5000 rounds before accuracy decline is noticeable, where as a 30-06 is typically half that ammount.
308 win has a good balistic coefficient so it is accurate and stable bullet.
If you reload for 308 or 30-06 the options of bullet types and powders avaliable are rediculous.
Either round is very good and will serve you well
but I think 308 is the best option for almost any thing you can use it for.
outdoors.stackexchange.com/users/9581/Michael
I personally don't think there's that much difference between the 2 calibers, they both use similar weight bullets.
I'd use either on most game in North America.
So I'd approach it from this angle, what caliber ammo can I find readily available in your area?
Now if you're talking primarily very large game such as bear, moose, bison, etc.
I'd probably go bigger such as the larger 30 calibers (338, 375, etc) or into the 40 caliber rounds.
If you're basically talking deer, elk, hogs, either of those rounds are fine.
outdoors.stackexchange.com/users/2566/Bill
Both .308 and 30-06 can chamber from 125 to 180 grains.
That is where the .308 stops.
The 30-06 can go up to 220 grains.
Therefore, with the 220 grain 30-06 you can take heavier and larger game such as elk, moose, black bear and though considered minimum at 220 a brown bear.
The benefit to you is one rifle is more versatile with 30-06.
outdoors.stackexchange.com/users/7921/Richard Sward
Both are good calibers.
The 30-06 is better with 200 plus grain bullets.
Although for 200 grain and above I use magnum calibers.
That's just me.
I like lighter bullets for flatter trajectory, because it can't hurt for placement on longer shots.
The 308 is easier on barrels with less recoil.
A 30-06 has a bit more energy and speed.
Both are very effective large game rifles with proper bullet construction and placement.
Very similar in all around performance.
outdoors.stackexchange.com/users/18255/Vince F
The two rounds are essentially the same.
To a newcomer, the differences are not going to matter.
If you are picking between these two calibers of the same model rifle, I would just get whichever has cheaper ammunition.
outdoors.stackexchange.com/users/68/whatsisname
As a relative newcomer to the shooting/hunting world, I am looking to buy my first big game rifle. Now, I know what  rifle  I want, just not what caliber to get it in.  The two calibers that I am left with after reading up on the subject are .308 and .30-06. So, what are their relative advantages?
What are the relative advantages of .308 and .30-06
outdoors.stackexchange.com
<hunting><shooting><rifles>
outdoors.stackexchange.com/questions/4840
outdoors.stackexchange.com/users/2654/razumny
Both are very effective large game rifles with proper bullet construction and placement. Very similar in all around performance. The benefit to you is one rifle is more versatile with 30-06, although it has slightly more recoil. The two rounds are essentially the same and to a newcomer, the differences are not going to matter.   Both are very similar, though 30-06 is more versatile and 308 has less recoil. Price should be a key consideration.
30-06 is more versatile. The 308 is best for newcomers because of lower recoil. Price is the main difference. Both are very similar.