.308 vs .30-06

JRI states:
Nope,sorry Bart,the 3092 fps 150 grain load is 1.7 grains below maximum charge,according to the load manual,pressure is 57,200 psi at maximum charge,so obviously my 3092 fps load is slightly under 57,200 psi.
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While the peak pressure may have been that high with that load in the barrel Hornady used, it is not obvious your barrel will have the same peak pressure. You're assuming (guessing?) it was. Several things in your shooting system were different that Hornady's. Case dimensions and neck tension. Bore and chamber dimensions. Powder and primer lot numbers. Firing pin impact.

What powder and primer did you use? And was the same powder used in both the .30-06 and .308?

Exactly what do you mean by:
Now when both are loaded to standard military specs,they're pretty much equal,however,the 308 is close to max,where as the 30-06 is downloaded.
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In what way is the .30-06 downloaded?

What's the military spec difference between a .30-06 and a 7.62 NATO round, peak pressure wise?
 
CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

I ran a couple loads through QuickLoad to get it's prediction. SAAMI dimensions and 24" barrel. OAL max or .308 seating depth, as appropriate.

With a 150gr Hornady SP,

Max velocity powder, RL-17
.30-06-60.6gr 3,109fps
.308Win-52.4gr, 3,029fps

With 110gr Hornady SP, Win748
.30-06, 59.3, 3,481 (max speed IMR30301 3,496)
.308Win, 52.2, 3,430fps

With 180gr Hornady SP, RL-17
.30-06-51.8gr 2790fps (Max Ramshot Hunter, 55.5gr, 2,798)
.308-47.7gr 2,752fp (max W76049.6gr 2,753fps)


Short version: There's not much difference.
 
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Back before CUP, psi was the deal. The factory loads for the '06 were published as being around 49,000 psi. When the .308 first came on the market, factory loads were published as being 55,000 psi.

Just guessing, but I've always figured that the lower pressure for the '06 had to do with all the old Springfields that were "out there". The GI loads were around 47,000 or 49,000, I disremember.

So, you load an '06 to 55,000 and you'll outrun a .308. Not enough for Bambi to notice, though.
 
Using Brians numbers for a 150 gr bullet the 308 gives up about 2.5% velocity but uses about 14% less powder and has about 12% less recoil. If you also factor in that with modern bullets there is simply no need for the heavier bullets that used to be a advantage in 30-06. A 150 gr, even 130 gr premium bullet from a 308 will kill anything on this continent.

I've hunted with a 30-06 since the 70's, have several that aren't for sale. But my 308 is 2 lbs lighter, shoots just as well and goes hunting a lot more often now. I cannot imagine any animal ever knowing the difference.
 
Brian, thanks for a decent comparison using QuickLoad. While it's based on known component behavior and predictions on results, it's a lot better than two barrels with unknown internal dimensions and other unknown variables.

Here's more reasonable comparisons between these two cartridges:

MIL-SPEC data for the 7.62 NATO M80 round, 22 inch test barrel:
WC846 powder, 146 grain bullet, 2750 fps at 78 feet
peak pressure 50,000 CUP

SAAMI spec for the .308 Win. round, 24 inch test barrel:
150 grain bullet, 2800 fps at 12.5 feet
peak pressure 52,000 CUP

MIL-SPEC data for the 30 caliber M2 round, 24 inch test barrel:
4895 powder, 150 grain bullet with 2740 fps at 78 feet,
peak pressure 50,000 CUP

SAAMI spec for the .30-06, round, 24 inch test barrel:
150 grain bullet, 2900 fps at 12.5 feet
peak pressure 50,000 CUP

MIL-SPEC data for the 30 caliber M72 round, 24 inch test barrel:
4895 powder, 172 grain bullet with 2640 fps at 78 feet, 24 inch test barrel
peak pressure 50,000 CUP

MIL-SPEC data for the 7.62 NATO M118 round, 22 inch test barrel:
4895 powder, 172 grain bullet with 2640 fps at 78 feet
peak pressure 50,000 CUP

SAAMI spec for the .30-06, round, 24 inch test barrel:
168 grain bullet, 2790 fps at 12.5 feet
peak pressure 50,000 CUP

SAAMI spec for the .308 Win. round, 24 inch test barrel:
168 grain bullet, 2670 fps at 12.5 feet
peak pressure 52,000 CUP

Please, fellas (Art Eatman?), do not get the older copper units of pressure (CUP) confused with the modern piezo transducer strain gauges measuring actual pressure in pounds per square inch (PSI). Shame, shame on both the military and commercial folks using PSI for their pressure numbers when they measured those little primer-size crushed copper pellets' thickness from the piston in the pressure test barrel crushing them, then compared the measurement to a tarage table supplied with each lot. They're not the same actual pressure except in about 30,000 units of each. For these two cartridges, the actual pressure in pounds per square inch is a few to several thousand more than the CUP numbers listed. For example, in the SAAMI loads above at 52,000 CUP for the .308 Win., the strain gauge numbers are 62,000 PSI for peak pressure.

Study the pressure measuring information in the following SAAMI document for both the .30-06 and .308 Win. rounds as well as how each is done:

http://www.saami.org/specifications_and_information/publications/download/206.pdf
 
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I have a pair matching Remington 700s.One in 308 the other in 30-06.Killed Georgia whitetails with both and they seem identicle in hunting performance out to 250 yards for me.I can tell a difference in recoil though.30-06 does hit harder.The 308 is my "go to" deer rifle.
 
CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

I was surprised to see that the trend in the QuickLoad predictions was that the .308 was actually getting CLOSER to the .30-06 as the bullets got heavier so I went ahead and also ran the numbers for Hornady 220gr RN:


.308- Best noncompressed load, RL17, 44.9, 2,492fps, 108% compressed load, Ramshot Hunter 47.9gr, 2,498fps
.30-06- Best noncompressed load, Ramshot HUnter 56.9gr, 2,585fps, 108% compressed load, N560, 60.0gr, 2,654fps

Even here, where we've heard that the .30-06 "walks away" from the .308, we have only 150fps difference and only 93fps without going compressed. Any given difference between two guns/barrels/chambers could make up for that difference.
 
Bart B, I'm not confusing anything (I hope). I'm citing figures from back before CUP came into use in talking about pressures. Data in later loading data books, and other writings, talk about CUP. But factory data in the 1950s and 1960s used psi.

I dunno. Way back when, in my metallurgy classes and some other courses, we measured psi via strain gauges.
 
Art, chamber pressure was measured using copper (or lead) units of pressure decades before piezo or strain types of electric gauges were used starting in about 1970. Electric gauges were used in other industries beginning in the 1950's but rarely then in ammo testing. Factory and military specs were still based on copper units for sometime after 1970 'cause that's the system they used, trusted and already had plus it worked very well for all safety issues. But the vast majority of them stated the numbers in print as "psi" value when in fact it was copper (lead) units of pressure or CUP (LUP). When comparing numbers of both system, such as between the commercial .308 Win. using electric systems stating 62,000 psi or copper crusher systems stating 52,000 with both cup and psi suffixes compared to the military 7.62 NATO crusher system stating 50,000 psi, the confusion and mistakes began. They still exist 'cause so many folks don't communicate nor understand the realities of each.
 
Bart,my results were with 6 different rifles,3 in 308 Win,and 3 in 30-06,never once could I match the velocity of the 30-06 load with the 308 Win,I ran into pressure problems before I could reach 2900fps with the 150 grain bullet in the 308.

I was using IMR 4320,IMR 4064 and W760,CCI 200 primers,even tried Winchester LR primers in both the 308 and 30-06,the 06 always posted considerably higher velocities than did the 308,and that was with the 6 rifles,so I don't know.

So for me,I'm sticking with the 30-06,as it always has worked well for me.I got rid of all the 308 Win rifles I owned.
I appreciate your input as well as others' input on the subject.
 
JRI:
Bart,my results were with 6 different rifles, 3 in 308 Win, and 3 in 30-06, never once could I match the velocity of the 30-06 load with the 308 Win, I ran into pressure problems before I could reach 2900fps with the 150 grain bullet in the 308.
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That happens all the time when using barrels of the same (or within an inch or two] length. There was never any objective in the development of the 7.62 NATO and .308 Win. round to equal the velocity of a .30-06 for a given bullet weigh or barrel length. Close was good enough.

What about your comment:
Now when both are loaded to standard military specs,they're pretty much equal,however,the 308 is close to max,where as the 30-06 is downloaded.
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Please explain your reasoning on this.
 
" But the vast majority of them stated the numbers in print as "psi" value when in fact it was copper (lead) units of pressure or CUP (LUP)"

Ah so. Danke.

As far as "downloaded" '06 ammo, my recollection of factory data from '50s/'60s was that the '06 was loaded to GI specs of around 49,000 psi, while the .308 was reported at 55,000 psi. I've no clue about today's loadings.

I'm lazy. I've been using the same loads in my '06 as back in 1950 when I first started. They work just fine, so why bother to change? :D

I get deeper dings in my 500-yard steel plate with my '06 than friends do with their .308s. Not enough to get excited about, but that's consistently been the case. Kinda hard for me to not believe that the '06 is generally a little bit stouter than the .308.
 
Art...... Get today's loadings from the info below:

Please download the following for MIL SPEC info on military cartridges. Note they state "psi" for pressure but they used copper units of pressure; they should be "cup" to be correct:

http://www.everyspec.com/ARMY/TM-Tech-Manual/TM43-0001-27_CHG-2_4432/

Then download SAAMI's document on cartridge specs. Starting at page 13, the cartridge pressure and velocity specs are listed. First for cup then later for psi numbers; very interesting indeed:

http://www.saami.org/specifications_and_information/publications/download/206.pdf

The info in the SAAMI document has excellent info on both pressure measuring types, techiques and specifications.

Of course, the .30-06 is "stouter" than the .308. It shoots bullets out faster given equal barrel and pressure numbers.
 
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My '06 flings 168's at 2,940 fps, 175's at 2,820 fps, and 190's at a tick over 2,700 fps...24" factory barrel....I shot 308's for nearly 20 years, and I've never seen one approach the velocities I get with the 30-06 loaded to 63k psi in a modern bolt action.

Both are fine rounds...but the 30-06 is the more potent of the two.

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I've never seen one approach the velocities I get with the 30-06 loaded to 63k psi in a modern bolt action.
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RidgeRunner, how'd you know the pressure was 63k psi; what did you measure it with? SAAMI's pressure limit for pressure transducer measurements on the .30-06 is 60,000 psi and its based on the limits of the .30-06 case. If you really had 63,000 psi, then it's quite possible standard average peak pressure loads for a .308 won't approach what that pressure produced.

Note that modern bolt actions will handle that much pressure for any cartridge. Some .308 Win. factory ammo has pressures at 63,000 psi as its case design's rated for 62,000 psi; the SAAMI spec which also has 66,000 psi for a maximum sample probable mean pressure.
 
Somebody sez, "Mr. Eatman," and I look over my shoulder to see if my father's around. :D I'm only "Mr. Eatman" to government employees, who don't merit the right to be familiar.
 
If the 30-06 case limit is 60k psi...explain how the 25-06 and 270 came to be, both are loaded well over 60k psi.

The SAAMI limit is based on something (probably older guns)...but its not the limits of that case.

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RidgeRunner, I'll answer your query.

Some of the commercial .30-06 match grade cases made by Winchester and Western Cartridge Company were made with thinner case walls than standard cases; typically 25 grains lighter than regular commercial cases and this frightened lots of folks. And some foriegn military .30-06 cases were not annealed to the specs that US military and commercial cases were/are.

Then there's the issue with low-numbered M1903 Springfields with not so well hardened receivers. SAAMI considered them when limiting peak pressure to 60,000 psi or 50,000 cup.

None of the other two commercial cartridges cases were made that way as far as I know. And the .308 Win.'s loaded to pressures higher than the .30-06 SAAMI spec, too, as are several belted case magnums.

Contact SAAMI then ask them as they set the spec; the guy there I've talked with over the years has answered my questions quite fast and well.

Still waiting on the answer to my question in post 55.
 
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Would it really be relevant to the discussion if I answered with QuickLoad, SWAG, or even White Laboratories...the point was, that the properly loaded 30-06 can beat the 308 not by 100 fps...but by 200-300 fps, depending on bullet weight...and its perfectly safe to do so, in modern bolt actions.

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Ridgerunner665 said:
Would it really be relevant to the discussion if I answered with QuickLoad, SWAG, or even White Laboratories...the point was, that the properly loaded 30-06 can beat the 308 not by 100 fps...but by 200-300 fps, depending on bullet weight...and its perfectly safe to do so, in modern bolt actions.
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Not according to QuickLoad it can't, not staying within SAAMI limits, which is the only definition of "safe" that matters.

The 30-06 gets about 150fps, max, over the .308, all else being equal to SAAMI spec.
 
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