308 vs 7mm Deer Hunting Out to 650 yards

[Legionnaire]

.308 165 gr Sierra Tipped GameKing @ 2,680 fps: 17.1 MOA drop and 1,022 ft lbs energy at 650 yards
7-08 165 gr Sierra Tipped GameKing @ 2,562 fps: 17.8 MOA drop and 1,074 ft lbs energy at 650 yards
7-08 150 gr Hornady ELD-X @ 2,770 fps: 15.2 MOA drop and 1,112 ft lbs energy at 650 yards
7-08 140 gr Nosler Ballistic Tip @ 2,825 fps: 15.6 MOA drop and 920 ft lbs energy at 650 yards

All factory loads, data pulled from MidwayUSA and run through JBM Ballistics calculator.

 

[bdyal1972]

From an accuracy stand point

The temperature stability and year in year out CONSISTENCY of black hills 175 match load makes it a DEER SLAYER in any barrel it agrees with

 

[erikblank]

I've never owned a 7mm mag. I reload and have three different .300's and a total eight .30 calibers. For me it doesn't make since to add a different caliber into the mix. That being said, I have shot a few 7mm mag. and hunted with guy's using them. Great round and would be the the best choice given the 2 options.

I would have no problem taking a shot at 650 yards, at a deer, with my .308. It just wouldn't be my first choice. It's just a right tool for the job thing. Yes the 2lb. hammer will work, but the 3lb-er makes life easier in this case.

 

[skippertwo]

Go with the 7mm, It's an excuse to buy another rifle.

 

[RYEWSKY25284]

For whitetail over large ag fields with a max range of 650 yards, what caliber would you prefer?

I have a Tikka 308 that shoots factory ammo MOA at 100 yards. I shoot high BC factory 308 loads. I am considering a Tikka 7mm Mag as well. I don't reload so ammo availability is important for me as well.

Would the 308 with a heavier high BC bullet do the trick on whitetail or would the 7mm Mag do better? The recoil from the lightweight Tikka in 7mm Mag could be a factor.

I'm not a big fan of heavy recoil....Having said that, 7mm....faster, flatter, farther

 

[Bob Wright]

A muzzle brake really tames them down. I'd go 7mm mag with a brake added.

 

[BigGriz]

+1 for the 7mm. Less drop and drift which is less chance for mistake in a hunting situation.

 

[DCAN]

Is ammo availability an issue in your area? It sure is where I live. 308 tends to be everywhere, or at least it used to be.
November is getting closer. It may not go well. Buttigieg may be the new gun zhar.
Oregon has already seen proposals limiting ammo purchases to 20 rounds a month, and only with a background check for every purchase. Just a thought.......

All that aside, the 7mm wins on paper, but the 308 has a lot of options going for it.

 

[Bux240]

I know I maybe getting repetitious but as I mentioned earlier this week, if recoil is the issue and muzzle breaks ruin the line of the gun (not to mention the noise factor) try getting a quality recoil pad (ie.: Gooey Pad, Kickeeze, Falcon Strike). They will reduce recoil on a 7 mm Mag to a quite tolerable level. My wife shoots a 300 Win Mag (shooting 220 grain bullets) equipped with a Gooey Pad all the time with no ill effects. Just a suggestion and my .02 cents worth.

 

[Deleted member 107796]

+1 for the 7rm on ballistics alone, as mentioned by many, but a 308 can kill very well. When you train, using a proper pad, recoil is no factor until you get into the elephant guns, IMO.

 

[Lionel Boyd Johnson]

I believe what TexSavage is suggesting is setting up a more balanced comparison between the .30 and the 7mm based on ballistic coefficient. The initial comparison was biased in favor of the 7mm by the choice of bullets. -Ed

 

[entoptics]

You could use a 215 Hybrid in the .308 and from what I've seen 2,400 FPS is easily attainable. That would give you 1,850 plus ft lbs at 600 yards...

I ran a 215 @ 2400 through JBM, and to get 1850 ftlbs at 600 yards, I had to go to 90°F and 11,000 feet elevation. Not sure that's applicable to whitetails in ag fields. At 2000 ft and 70°, it's more like 1500 ftlbs. To get 1850 at 600, I had to start it at 2650 fps, which I don't think anyone will get in a 308 Win, unless they are rocking a 30" tube or something.

Also, the OP does not reload, and I'm not aware of a 215 factory offering, and didn't see anything over 185 grain on MidwayUSA (aside from subsonics).

I believe what TexSavage is suggesting is setting up a more balanced comparison between the .30 and the 7mm based on ballistic coefficient. The initial comparison was biased in favor of the 7mm by the choice of bullets. -Ed

If you are referring to my MERC Simulations in post 2, I chose two commonly available bullets, both heavy for caliber, and both nearly identical weight.

Since the OP does not reload, here's a comparison of two Hornady Precision Hunter facotry offerings. A 178 ELDX (0.535 BC) @ 2600 fps in the 308 vs the 7mm RM with the 162 ELDX (0.613 BC), @ 2930 fps. Again, all variables the same (10 ± 3 wind, 1 MOA rifle/shooter, 10 fps MVSD, 30° wind angle uncertainty, ±5 yards range uncertainty).

As you'll see, the outcome is not much different. Both are worse than my previous simulation, as the 308 is going slower than my estimate, and the 162 7mm has a worse B.C. and is also on the slow side compared to reloads, but the difference between them is still substantial.

7 mag has 15% better hit percentage at 650 yds

7mm outruns the 308 by 200 yds in energy, and 300 yards in expansion velocity (308 doesn't even make it to 650 with enough velocity to expand).
In the simulated conditions, 7mm allows an 8 out 10 hit confidence ~75 yards further than the 308.

Not much difference in the recoil results this time around. 7mm is quite a bit more obviously.

 

[erikblank]

Oregon has already seen proposals limiting ammo purchases to 20 rounds a month, and only with a background check for every purchase. Just a thought.......

Yes but with your local government getting rid of all police, to make BLM happy, who will enforce it?

 

[QSYB1]

Brake brake brake. Don't any of you own cans?