Range Report 7mm-08 vs .308 Help

[Raven 6]

Not sure this is the place so if not please move.

I've always been for the .308 but I'm wanting to try something a little different. Please give me the good, the bad and the ugly of each one and why you would choose either. Thanks

 

[Helmet]

Re: 7mm-08 vs .308 Help

I took the barrel off my HS Precision Savage 308 and put on a Criterion 7mm08 barrel. I did this because 308 can never be as good as a 7mm08. A 7mm drifts less and drops less given the same MV. A 175 SMK 7mm has a higher BC than a 208 Amax in 308.

The only downside to a 7mm08 compared to a 308 is the selection of bullets and ammo. A 308 has an endless selection of stuff you can use, but none of it will make it a 7mm

. If you are reloading then 7mm08 is much better.

Lapua does not make brass for the 7mm08. You can neck up Lapua 260 brass, but I got the Nosler 7mm08 brass and I honestly think it's nicer. I can't say if that's true for every Nosler caliber, but in 7mm08 it's quality stuff.

 

[Graham]

Re: 7mm-08 vs .308 Help

For what purpose?

Balistically, there's no contest.

 

[RobertB]

Re: 7mm-08 vs .308 Help

Dont forget about the 260. Dont know what you will be doing with the rifle but i went the 260 route and have been pleased. Good luch

 

[Raven 6]

Re: 7mm-08 vs .308 Help

Long distance targets say 800-1200 yrds.

 

[Graham]

Re: 7mm-08 vs .308 Help

The 7-08 will walk all over the .308 at that distance.

 

[TRAAV]

Re: 7mm-08 vs .308 Help

yes there is no comparison

 

[TRAAV]

Re: 7mm-08 vs .308 Help

in favor of the 7-08

 

[mdesign]

Re: 7mm-08 vs .308 Help

If your 7-08 happens to like the 162 Amax, you get the combination of higher MV (than 175gr) and good BC that really pays off down range in the wind.

Here is a comparision I did back when I was making a similar decision. You can debate the actual MV by caliber (a number of folk did) but the picture is pretty clear from a comparison perspective. The 260 and 7-08 run pretty close in all areas, sometime one is better than the other but they are pretty much the same. I went with the 7-08 because it had higher energy but nothing wrong with the 260 either.

 

[turbo54]

Re: 7mm-08 vs .308 Help

As far as I'm concerned, the 708 is what the 308 *should* have been.

Nothing a 308 will do that a 708 won't, but a 708 will do lots of things a 308 won't. Don't forget Jeff Cooper was in favor of 708 for his "scout rifle" concept.

Past 750 yards, the 708 is much, much more forgiving.

I've read many times that 708 is a "light recoiling" cartridge. I beg to differ. When you sling a 162amax @ 2800fps, or a 175smk @ 2650-2700, there is every bit as much recoil as a 308 with a 175 @ 2650-2700 (DUH!! momentum/recoil = mass*velocity).

I'll also choose a 708 over a 260 any day. While the 260 is a bit flatter, the 708 drifts a little less, and has appreciably improved barrel life. The 260 does indeed have noticeably less recoil than a 708 though.

 

[turbo54]

Re: 7mm-08 vs .308 Help

Mdesign: What bullet/mv did you use for the 243 in your graph?

I ask because a fellow with a 243 using 115dtacs @ 3050fps was shooting next to my 284 with 175smk @ 2800. He was pretty close to me on wind out to 1000. I started pulling away past 1000, but even at 1220, I had ~1.8mrad wind, and he had 2.1.

 

[Adam B]

Re: 7mm-08 vs .308 Help

I call BS on the 243 info

Drop and Wind-Drift calculated with Point-Blank Software for 70° F temp, and 1000' altitude. BCs were 0.585 for 115 DTAC, 0.535 for Berger 105 VLD.

 

[TRAAV]

Re: 7mm-08 vs .308 Help

The 243 with with most any high BC bullet is going to be as good or better than the 260/708. Defiantly not worse. I'm not sure how your getting these numbers.

 

[mdesign]

Re: 7mm-08 vs .308 Help

And it was the 243 data that was hotly debated last time...

Don't have the data in front of me but I think it was a MV of 2975 and a BC of 510. Maybe there was an error in the data, don't know, did not go back and look. Maybe I can get a chance to do that this weekend.

The OP was asking about 308 vs 7-08 so hopefully he found that part of the chart helpful.

 

[Raven 6]

Re: 7mm-08 vs .308 Help

The information is great guys. If you have more post it up the more information the better to help with my choice.

 

[Banded82491]

Re: 7mm-08 vs .308 Help

also what rate of twist for 140/150 gr. bullet weight?

 

[MontanaMarine]

Re: 7mm-08 vs .308 Help

It's pretty hard to make a good case against the 7-08. the 162 AMax at 2800 fps is a great use of 45gr of powder. Excellent exterior ballistics, good barrel life, moderate recoil, mag box friendly. What's not to like.

I push the 208 AMax to 2700 fps in the 308, but it requires a long oal, and single load. One of these days I'll get a Wyatt magazine box and cure that.

 

[Raven 6]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fowler</div><div class="ubbcode-body">also what rate of twist for 140/150 gr. bullet weight? </div></div>
That's another good question, what twist rate are you guys shooting with the 150's and 162's?

 

[turbo54]

Re: 7mm-08 vs .308 Help

1:9 minimum for a 708 that may see 162s.

1:8.5 is better.

 

[clmayfield]

Re: 7mm-08 vs .308 Help

I have been thinking about 7mm-08. The only thing the 308 has on it is barrel life and a wide array of ammo and components available.

But once I think about 7mm-08, why not .284WIN? You can throat it for a short action and while it is tight in a short action, and you are limited in bullet selection in short action, you will likely have something that exceeds the 7mm-08.

And after I am done thinking it to death, I decide to keep on with 308...

 

[The Lawn Ranger]

Re: 7mm-08 vs .308 Help

284 should be shot through a long action in my opinion. Especially if loading through a box mag.

I am running the 168 VLDs at 2900 fps. Pure bliss.....

 

[turbo54]

Re: 7mm-08 vs .308 Help

My SA284 is doing the 175smk @ 2800fps with ease. Could certainly go faster, but 7.8mrad from 100-1000 is good enough for me.

Based in my research, and I think I've read everything ever written about 284, 2800+ from a 175 is right in line with what the cartridge can do without RL17.

 

[rkgsmith]

Re: 7mm-08 vs .308 Help

Is there anything wrong with just resizing once fired 308 brass and turning it into 7mm08 cartridges. I can get all the 1x 308 brass for free and would not have to shoot it more than once. Is there any real disadvantage to doing this? Is there a need to get 7mm08 brass?

 

[The Lawn Ranger]

Re: 7mm-08 vs .308 Help

Different strokes......

 

[turbo54]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rkgsmith</div><div class="ubbcode-body">Is there anything wrong with just resizing once fired 308 brass and turning it into 7mm08 cartridges. I can get all the 1x 308 brass for free and would not have to shoot it more than once. Is there any real disadvantage to doing this? Is there a need to get 7mm08 brass? </div></div>

Not ideal. 243, 260 and 708 brass is .030" longer than 308. Also, necking own thickens necks. If you have a chamber on the bottom end of the SAAMI allowable size, you may have to neck turn. I had to neck turn FC 308 brass I necked down for my friends CBI barreled 708 savage.

 

[turbo54]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: m14er</div><div class="ubbcode-body">Different strokes...... </div></div>

Not sure what you mean...

 

[azimutha]

Re: 7mm-08 vs .308 Help

I do like the Berger 175 OTMs in .308 and there are some other reasons I stuck with it on my last build. But man, when you look at the BCs for 7mm projectiles! I might do another in 7mm-08.

 

[The Lawn Ranger]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: m14er</div><div class="ubbcode-body">Different strokes...... </div></div>

Not sure what you mean...</div></div>

We should move this discussion over to the 284 thread as the OP is concerning 308 VS. 7-08

 

[Nortex]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">1:9 minimum for a 708 that may see 162s.

1:8.5 is better. </div></div>

My 1:10 works just fine with 162's not sure if that's normal but they seem to shoot just fine.

 

[turbo54]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nortex</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">1:9 minimum for a 708 that may see 162s.

1:8.5 is better. </div></div>

My 1:10 works just fine with 162's not sure if that's normal but they seem to shoot just fine. </div></div>

Not unheard of, not exactly "normal" though. 1:10 is a gamble. Glad it's working out for you though!

 

[mdesign]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rkgsmith</div><div class="ubbcode-body">Is there anything wrong with just resizing once fired 308 brass and turning it into 7mm08 cartridges. I can get all the 1x 308 brass for free and would not have to shoot it more than once. Is there any real disadvantage to doing this? Is there a need to get 7mm08 brass? </div></div>

Not ideal. 243, 260 and 708 brass is .030" longer than 308. Also, necking own thickens necks. If you have a chamber on the bottom end of the SAAMI allowable size, you may have to neck turn. I had to neck turn FC 308 brass I necked down for my friends CBI barreled 708 savage. </div></div>

^^ what he said...necked down 308 Lapua brass will not chamber in my gun without trimming. I run WW 7-08 but have heard good things about Nosler.

 

[Nortex]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: nortex</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: turbo54</div><div class="ubbcode-body">1:9 minimum for a 708 that may see 162s.

1:8.5 is better. </div></div>

My 1:10 works just fine with 162's not sure if that's normal but they seem to shoot just fine. </div></div>

Not unheard of, not exactly "normal" though. 1:10 is a gamble. Glad it's working out for you though! </div></div>

I was originally planning on running lighter stuff for varmints and just gave the 162's a shot and was impressed enough to stick with them. Not sure on this but weren't 7rem mag's built with 1:10 twists? For some reason I seem to remember that number with that cartridge.

Edit: It appear that it was the 7mm Weatherby that commonly used the 1:10 twist not the Remington.

 

[Bruiser_Joe]

Re: 7mm-08 vs .308 Help

this thread just makes me itchy to do a comparison on some new rifles i have coming in

6cm vs. 260 vs 308 vs 7-08

who wants to play

 

[sandwarrior]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BigJoe</div><div class="ubbcode-body">this thread just makes me itchy to do a comparison on some new rifles i have coming in

6cm vs. 260 vs 308 vs 7-08

who wants to play

</div></div>

What you'll find is what we've all said the last few years here.

.308 will be the 'fat kid' at the track meet. The .260 with 140/142's and the 7mm-08 with 168's will be neck and neck. The 6CM is will shoot all-out flatter than all. But, it drifts in wind a lot worse than the 6.5 or 7mm-08. I'm even finding that with my 6mm Ackley. 105's sent at hellspeed drift more than 168/175/180 BER's/SMK's

I shoot a 7mm-08 based off a Savage action with a 1-8" twist barrel. It loads Berger 180's just fine in a DBM in case you want to shoot a group of five. It'll beat drift of a 6.5mm any day. But the 6.5 shoots flatter.

 

[Bruiser_Joe]

Re: 7mm-08 vs .308 Help

Oh I know still be fun to do

 

[Helmet]

Re: 7mm-08 vs .308 Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: M.Williams</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fowler</div><div class="ubbcode-body">also what rate of twist for 140/150 gr. bullet weight? </div></div>
That's another good question, what twist rate are you guys shooting with the 150's and 162's? </div></div>We tend to argue about this around here as guys are in to different camps about this and that's fine. Personally I think that a 1-9" twist is the fastest twist you should get. Savage rifles come with a 1-9.5" twist and they shoot the 162 Amax just fine. I know a guy at the my rifle range who did a 1-10.7" specifically to shoot the 162 Amax. I wouldn't suggest getting a twist that slow, but I'm just making my point. Bullet length is more important than weight. longer bullets require more spin than shorter bullets to stabilize. A 162 Amax is about 1.28" without the plastic tip. Try it yourself: http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
The reason nortex can stabilize a 162 Amax with a 1-10" twist is because it's plenty of twist for that bullet.

I think a twist of 1-9" is best just to make sure you have enough. Even if you plan to shoot 150gr bullets now, you may change your mind later and want to use a 175SMK. At 1.453" it needs a 1-9" to make sure it will stabilize on a really cold day.

 

[Raven 6]

Re: 7mm-08 vs .308 Help

Thanks everyone. Looks like you have made my decission alot easier.

 

[mdesign]

Re: 7mm-08 vs .308 Help

Good summary sandwarrior..

 

[Banded82491]

Re: 7mm-08 vs .308 Help

thanks, this has been a great help

 

[7mmRM]

Re: 7mm-08 vs .308 Help

Sandwarrior nailed it.

As for brass, if my 7mm08 could read headstamps it would think it was a 308.

Win/BHM, R&P 308 have worked fine for me. Lapooey is a no go with out neck turning.

I had a God aweful shitty lot of WW 708 brass that soured me a bit. Just so happened, that I have a BUNCH of BHM 308 brass- been necking them down ever since.

 

[MK75]

Re: 7mm-08 vs .308 Help

I would say if the availability of factory ammo every becomes an issue for you. .308 would be he way to go. Otherwise I have always been a huge fan of the 7-08.

 

[Pat II]

Re: 7mm-08 vs .308 Help

I use standard Winchester 7mm-08 and neck it down on my .260 and it works great. I am getting .6 moa with my load. I dont see why it wouldnt work as well without being necked down.