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PatientWolf
November 13, 2012, 07:16 AM
I'm curious...

Is there anything the 30-06 will do (realistically) that the .308 Win won't do? I always assumed the .308 could do anything the 30-06 could do but just had higher pressures and maybe a little more kick since you might need to use slightly faster powder.

jmr40
November 13, 2012, 07:38 AM
Not much. With factory loads you are looking at about 100 fps more speed with equal bullet weights from the 30-06. In the real world, inside of 200-300 yards nothing you shoot at will ever know the difference. At longer ranges the 30-06 will be effective on game about 50 yards farther away and have very slighlty flatter trajectory.

I handload for both and can see a bit more gains with the 30-06. Generally speaking with handloads I can improve on 30-06 ballistics by about 100 fps over factory, but can only beat 308 factory loads by about 50 fps. So by handloading you can see a slighlty bigger gap in performance.

The 308's 2 biggest advanages are slightly reduced recoil, and the potetial for a smaller, lighter rifle. If I were considering 2 identical size and weight rifles I cannot see any reason to no just get the 30-06. But there are several companies offering scaled down, trimmer lighter offerings in 308. You cannot get a 30-06 rifle that trim and light. My Kimber in 308 is still under 6 lbs including a scope and mounts. A 30-06 including optics under 7 lbs would be hard to put together. Closer to 8 lbs is more typical.

Rifleman1776
November 13, 2012, 08:49 AM
The 0-6 is bigger and is better suited for larger game. e.g. moose, elk. Some even say it is fine for grizzly bears.
It is very versitile to load. I load mine 'down' for smaller game and closer ranges. Mild recoil that way and less ruined meat.
The .308 is a fine caliber that will do almost as much as the proven 30-06.

Skadoosh
November 13, 2012, 09:07 AM
The 30-06 does everything what the 308 does, its just does it bit better...including tenderizing your shoulder.

TheBear
November 13, 2012, 09:31 AM
.308win all day long!
the only reason i see for using a 30.06 is the option to shoot bullets of more than 200gr

coyota1
November 13, 2012, 09:45 AM
The 30 06 was shortened to the 308 by the military to make a more compact and lighter rifle and cartridge. Like the 223 it became a sporting round due to it's avialability. As said by previous posts, the 06 can do anything the 308 can do and more. The 06 isn't going away anytime soon so I'd opt for it, but I wouldn't be dissatified with the 308 if I happened up on one.

jmortimer
November 13, 2012, 10:10 AM
One you get above 180 grain bullets the .30-06 leaves the .308 in the dust.

kraigwy
November 13, 2012, 10:21 AM
For practical purposes, there is no , ZERO, difference.

If you'll not, in the Berger Reloading manual there is a 200 fps difference between the 308 & '06 using Berger's 230 grn bullet.

If you look a little further, you'll see Berger used a 26" barrel on the '06 and a 24 inch barrel on the 308.

The difference is with that bullet, the '06 remains super sonic to 1000 where the 308 remains super sonic to 800.

That probably can be extended a tad if you used a 26 inch barrel on the 308.

For hunting, both have the energy needed to do what needs to be done to 500 yards, 300 being a reasonable hunting range.

We can play with a calculator all day showing one is better then the other, but again, what is practical.

Years ago, the army did some test on accuracy of the 30 cal bullet, working on loads for the International 300 Meter Matches. They found that the 30 cal seemed most accurate at 2200 fps.

I have target rifles in both calibers plus a 300 WM. In my years of shooting 1000 yard matches, the best score I've fired was with the 308 out of my M1A. But that was in perfect conditions.

So in reality, is one really better then the other??? Flip a coin.

Brian Pfleuger
November 13, 2012, 10:36 AM
One you get above 180 grain bullets the .30-06 leaves the .308 in the dust.

True enough but considering that any animal in North America can be and has been cleanly killed with 150gr or smaller .308 caliber bullets, that fact really has no relevance to most American shooters. 150-180gr bullets are far more common in both cartridges than bullets heavier than 200.

McShooty
November 13, 2012, 10:48 AM
Here is a viewpoint. I think Mr. jmortimer is on the right track. As you go up the scale of vintage thirty-calibers, ability to handle heavier bullets increases. The .30-30 is a 150-grain rifle, as is the .300 Savage pretty much. The .308 is perhaps happiest at 165 grains. The .30-06 handles 180 and 200-grainers better. The .300 H&H will be best for 200- and 220-grainers. I could have said .300 Win Mag here, but it suits me to be very old fashioned. There is some overlap, of course, and the appearance of improved powder technology, as with Hornady's Superformance ammo and Hodgdon's Superformance powder, has increased the overlap.

Woody55
November 13, 2012, 10:57 AM
"Thirty Ought Six" sounds way cooler than "Three Oh Eight".

I think it's the "ought" that does. It's older and provides an emotional connection with John Browning which is always an advantage.

Saskhunter
November 13, 2012, 11:09 AM
For elk and moose, the .30-06 has an advantage with heavier bullets. For deer and smaller, there is no real difference.

jmortimer
November 13, 2012, 11:15 AM
^ You guys are right, as usual.

Here is Hornady Superformance 165 grain .308 24" Barrel
MUZZLE 100 200 300 400 500
2840/2955 2635/2544 2439/2180 2252/1858 2079/1574 1902/1325
MUZZLE 100 200 300 400 500
-1.50 1.80 0.00 -7.60 -22.10 -44.70

And the Hornady Superformance 165 grain .30-06 in a 24" barrel
MUZZLE 100 200 300 400 500
2960/3209 2750/2769 2599/2380 2357/2034 2173/1729 1997/1461
MUZZLE 100 200 300 400 500
-1.50 1.60 0.00 -6.90 -20.10 -40.70

And Buffalo Bore with 180 grains

PREMIUM 308 WIN. SUPERCHARGED Ammo - 180 gr. SPTZ
2710 fps - Kimber 84 Montana, 22 inch barrel

PREMIUM 30-06 SUPERCHARGED Ammo - 180 gr. SPTZ
2822 fps - Winchester All Terrain, (circa 1995) 22 inch barrel

Old Grump
November 13, 2012, 11:23 AM
It can shoot 200+grain bullets faster than a .308 but with 125 to 180 gr bullets its a wash, target won't know the difference.

GeauxTide
November 13, 2012, 02:20 PM
I can't tell any difference in recoil between the two in the sporters that I own. My particular '06 (700LH) shoots 150 Hornadys in 3/4" cloverleaves. The 308 (788) likes 165 Corelokts. I can load my '06 past 2800 with 180s, so my preference would be the '06 until I pick up my Scout Squad.....;)

hornetguy
November 13, 2012, 02:39 PM
Thirty Ought Six sounds way cooler than Three Oh Eight

I think you're on to something! We should start calling it the "three ought eight" ! :D

As to the topic... as was stated very eloquently by kraigwy (and oldgrump), unless you are wanting to shoot bullets over 200gr, just flip a coin. ;)

If reloading, it might be slightly cheaper to load the "three ought eight"... smaller case, yada yada... but the difference would probably be miniscule. Performance is a wash.

Slamfire
November 14, 2012, 09:46 AM
I can get 190's and 200 gr SMK to higher velocities in the 30-06 than the 308 Win.

That might make a difference in a hunting rifle.

As a target rifle I was talking to friend who is a Wimbleton Cup winner. He went through a 30-06 phase and told me that while he could and did clean the 600 yard target (ten ring 2 MOA) his X count was always 9 or 10X, could not get it higher. He has shot some awesome high X count cleans with a 308.

He had not shot 30-06 at 1000 yards and expressed the opinion that the extra 100 to 150 fps you get with a 30-06 might give a better score, but since we have not done the comparision, we don't know.

If it takes a Nationally ranked individual to see differences between the cartridges, I would not worry about which cartridge I am using, as I won't see any differences.

robertsig
November 14, 2012, 09:54 AM
Buying a single bolt-action gun? Flip a coin.

If you plan on buying a semi-auto battle rifle, a bolt gun, a Saiga, etc and want a common caliber? Go with the .308.

OsOk-308
November 14, 2012, 10:44 AM
I've had the '06, but not a .308, from what I've heard, .308 has slightly less recoil. As robertsig said, if you're planning on buying a semiauto battle rifle (FAL, M1A, HK 91 etc) get the .308, unless you want to shoot an M1 garand that can shoot commercial rounds. If not, go either way, the 30-06 has slightly more punch, but it will be unnoticeable by the recipient, even in the military kills have been recorded with the .308 out to 1000 yards, so I'm sure there isn't too much difference either way.

Moby
November 14, 2012, 11:04 AM
30.06 may sound cooler than .308, but can you make a 30.06 look like this?

Here's my Armalite AR 10. Ain't she pretty?
Attached is a Millett 6-20 X 50 TRS scope with an iluminated retical.
For a sub $300 scope I am very impressed by it. Waterproof, nitrogen filled and a lifetime warantee. Very clear optics. Zoom knob is a bit stiff however.

http://i154.photobucket.com/albums/s260/AircavMoby/AR10withMillett_zps196c3313.jpg

Wanted to go to the range and try some iron sights after I put on a new handguard.

http://i154.photobucket.com/albums/s260/AircavMoby/WP_000174.jpg

Josh_Putman
November 14, 2012, 11:10 AM
You say potato, I say small block chevy. :confused::D

On a serious note, I have always heard that the .308 is a more inherently accurate round than the 30.06. Something to do with case design, shape, or something of that nature.

Slamfire seems to have somewhat confirmed that with his post about his friend that is a nationally ranked shooter.

Moby, that is an awesome rifle you have there. I had an Armalite AR-10(T) that I had to sell a few years back. I still kick myself for doing it, but it was for the right reason. (Son was born, I was unemployed)

I plan on having another one sometime. Maybe not the target version, but an AR-10 nonetheless.

Art Eatman
November 14, 2012, 12:32 PM
With the usual factory 150-grain "deer cartridge" in a common barrel length around 22", there's not a nickel's worth of difference.

In my 26" barrelled '06 with max handloads, I'd get about 300 ft/sec higher muzzle velocities than a .308. Probably even better with 180s, although I never chronographed them. (Judging by comparative trajectories at my 500-yard range.)

coyota1
November 14, 2012, 01:00 PM
Well, if I can get a shorter bolt throw and a stiffer action with the 308, then I would lean toward it.

Clark
November 14, 2012, 01:30 PM
I own so many 308s and so many 30-06s that I have lost count.
I have never been able to get good groups with either.

I think it must be me.
I can get good groups with 300WM.

Bart Bobbit was competing at Camp Perry decades ago with a 308 and making posts about how the 308 is slightly more accurate than the 30-06.

Bart B.
November 14, 2012, 04:04 PM
There's about a 100 fps difference in muzzle velocity for SAAMI barrel specs for both the .308 and .30-06 with 180-gr. bullets at their normal max pressures. Some folks with tight .308 Win. barrels shoot a 180-gr. bullet from factory ammo faster than a loose .30-06 barrel with factory ammo with 180's; a very normal situation.

The .308 Winchester was made a commercial cartidge during the development of what became the 7.62 NATO round by Winchester (I used to think it was Remington). And it was based on the .300 Savage case as shown in:

http://riflemansjournal.blogspot.com/2011/02/history-30-80-wcf-origin-of-308.html

'Twas the use of the .308 Win. and 7.62 NATO in NRA and military rifle matches starting in 1963 that 3 years later, few .30-06 rifles were seen in competition when either one was allowed. In 1966, the NRA and military bullseye targets' scoring rings were reduced by about half for those used up through 600 yards; too darned many unbreakable ties were shot. 5 years after that, the scoring rings on the 800 through 1000 yard targets were reduced the same amount. Bullets up to 250 grains have been used with great success in matches from both cases.

Afield after game, there's not much difference. Both can shoot bullets heavier than 200 grains with great accuracy in the field, but the .308 Win. needs a longer throat to do so. Before the .30-06 became commercialized, the .30-40 Krag was a favorite on the bigger game animals and many moose and bear went down from a well placed shot from one.

Bart B.
November 14, 2012, 04:52 PM
coyota1 comments:Well, if I can get a shorter bolt throw and a stiffer action with the 308, then I would lean toward it.Note that a long action Win. 70 with a short stopped bolt throw for .308 ammo is stiffer than a short or long Rem 700 action.

allaroundhunter
November 14, 2012, 05:01 PM
Attached is a Millett 6-20 X 50 TRS scope with an iluminated retical.


............?........... Millett does not make a TRS in the 6-20x50 flavor. The TRS-1 is 4-16x50, and the TRS-2 is a fixed 10x. They also make the LRS which is a 6-24x56.....

old roper
November 14, 2012, 05:01 PM
PatientWolf, You spec out a 308 last month on a build are you changing your mind?

scotts_4x
November 14, 2012, 05:21 PM
Load the 06 to the same pressure you are seeing in the .308 and watch is very quickly walk away from the .308.
the reason manufactured ammo is loaded to such a low pressure number is so it won't blow up a garand. Modern 06 rifles will no doubt handle the same chamber pressure as its same model of rifle in .308, and make the .308 seem meager in comparison.

-scott

PatientWolf
November 14, 2012, 08:46 PM
I haven't really changes my mind I just haven't done anything about it yet. I may go the used rout to keep cost down and wanted people's opinions on the question posed since I seem to see a lot more 30-06 on the market than .308. Based on all the responses, I think .308 is still the right cartridge for me. Maybe I'll find the right rifle at the gun show in town this weekend.

Bart B.
November 15, 2012, 08:36 AM
Scotts 4x comments:Load the 06 to the same pressure you are seeing in the .308 and watch is very quickly walk away from the .308.

the reason manufactured ammo is loaded to such a low pressure number is so it won't blow up a garand.

Modern 06 rifles will no doubt handle the same chamber pressure as its same model of rifle in .308, and make the .308 seem meager in comparison.

I think you need to recheck your information sources. What you've stated disagrees with what I've observed and found out; especially the manufactured ammo being low pressure to be safe in Garands. Military 7.62 and commercial .308 Win. ammo used in Garands was never loaded to low pressures. In fact, it had higher peak pressures than .30-06 ammo.

Note also that Garand barrels were proof tested with the same peak pressure .30-06 loads as commercial factory sporting rifles.

JRI
November 15, 2012, 06:56 PM
In my years of handloading,39 years to be exact,the 30-06 will leave the 308 Winchester in the dust,when both are loaded to their full potential.

For example,in my 3rd edition Hornady reloading manual,using the #3031 150 grain Spire Point,in both the 30-06 and 308,the maximum velocity listed is 3100fps in the 30-06,and 2800fps in the 308,and this has been my experience of approximately 150 to 300fps difference between the two on my chronograph.

Now,using the #3070 180 grain Spire Point,maximum listed velocity is 2800fps in the 30-06,and 2500fps in the 308.

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.

Over the years,I have thinned down my collection of rifles chambered in 308 Winchester,matter of fact,I no longer own rifles chambered in 308,because I can download the 30-06 to match the ballistics of the 308,but I couldn't load the 308 to match the ballistics of the 30-06.

Jeff

coyota1
November 15, 2012, 07:29 PM
Note that a long action Win. 70 with a short stopped bolt throw for .308 ammo is stiffer than a short or long Rem 700 action.

I wasn't aware of this. Are you speaking of all model 70's?

crowsing
November 15, 2012, 09:05 PM
If I wanted to shoot over 200 gr I would pick something else other than the thirty ought tumbler. Ought six has been around forever and there r better calibers out there that r faster and flatter than old ought. The only advantage to the ought is u can pick up a box of ammo almost anywhere. Look into the 7 mag

Bart B.
November 15, 2012, 09:13 PM
JRI For example,in my 3rd edition Hornady reloading manual,using the #3031 150 grain Spire Point,in both the 30-06 and 308,the maximum velocity listed is 3100fps in the 30-06,and 2800fps in the 308,and this has been my experience of approximately 150 to 300fps difference between the two on my chronograph.Your 30-06 barrel might have smaller bore and groove diameters. Who knows what peak pressure each had. A bad comparison. And Hornady's data is also skewed for the same reasons.

Nobody shooting their own factory sporters can get a realistic comparison between these two (nor any other two) rounds unless their ammo is loaded to and barrels's chambers and bores are at SAAMI specs, peak pressure's at SAAMI specs and the barrels are mounted in a fixed receiver. If using SAAMI spec ammo and barrels, then you're comparing just the two cartridges. When two different chamber, bore and groove dimensions are used as well as not verifying they produce SAAMI pressure specs, you're comparing too many dissimilar things at the same time and the data will be skewed. To say nothing of the muzzle velocity errors caused by humans holding the rifles.

SAAMI data for 150's from a .308 Win. at 62,000 PSI says 2800 fps and the .30-06 with a 150 at 60,000 PSI says 2900 fps. Both used the same batch of 150-gr. bullets. SAAMI spec pressure and velocity barrels for both are 24 inches long and have .3000" bore and .3080" groove diameters. Barrels are mounted in a Universal receiver hard mounted on a bench; it don't recoil at all. So based on each cartridge's design specs and compared in identical systems, the .30-06 shoots 150's a hundred fps faster than the .308 Win.

JRI
November 15, 2012, 10:21 PM
Well Bart,thanks for the input,however,my chono,says 3092fps for a 10 shot string average for my load in my 30-06,150 grain spire point,#3031,cases have been reloaded 11 times thus far with this load,so, much better than what I ever received out of a 308.

Btw,this is with a 24" barrel.

Bart B.
November 15, 2012, 11:23 PM
JRI, 'twould be interesting to see what the peak pressure is for that 3096 fps 150. I've got that velocity with 155's in one my .308's with a 32 inch barrel using a known safe, normal max pressure load in a tight groove and bore dimension barrel.

I've shot 168's's from .308 Win. cases out the muzzle of a 24 inch barrel at 2900 plus fps; the barrel's bore and groove was only .0001" tighter than SAAMI spec. That's from a high pressure proof test round producing 65,000 CUP (81,000 PSI). With normal SAAMI peak pressures and barrels, it leaves about 2670 fps. Therefore, I think your 3096 fps 150 from a .30-06 case and 24 inch barrel's close to proof loads for it.

Art Eatman
November 16, 2012, 12:39 AM
" Therefore, I think your 3096 fps 150 from a .30-06 case and 24 inch barrel's close to proof loads for it."

Just guessing, based on my own results through the years, but odds are that the load is likely around 55,000 psi--about the same as the .308.

JRI
November 16, 2012, 07:38 AM
Therefore, I think your 3096 fps 150 from a .30-06 case and 24 inch barrel's close to proof loads for it

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.

You mentioned you achieved similar velocity in your 308 with 155 grain and a 32 inch barrel,now,take my 3092 fps 30-06 load,and shoot it out of a 32 inch barrel,and it will STILL smoke the 308 Win.

As they say in the racing circles,"there is no substitute for displacement",the same pretty much holds true here. The 308 does not have the case capacity the 30-06 has.

Jack O'Conner
November 16, 2012, 08:00 AM
I've owned my .308 since 1971 and its taken game from moose to mule deer. Very accurate and plenty of power. In contrast, I owned a 30-06 briefly and found the excessive recoil too much for me and sold it. I'm no fan of recoil.

I can load 200 grain Speer bullets in my .308 but velocity suffers. But I discovered that Nosler Partition 180's shoot flatter and penetrate deeply. So these Premium 180's are my favorite for truley big animals.

The hunter with a 30-06 rifle can shoot heavy 220 grain bullets. This may be considered an advantage by some. But I'm not convinced I'll ever need to shoot 220 grain bullets.

30-06 has been proven as a reliable big game cartridge wherever game is hunted. It's been around for over 100 years.

.308 has been proven as a reliable big game cartridge wherever game is hunted. It's been around for over 50 years.

Jack

Bart B.
November 16, 2012, 08:33 AM
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.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.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?

Brian Pfleuger
November 16, 2012, 09:30 AM
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.

Art Eatman
November 16, 2012, 10:16 AM
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.

jmr40
November 16, 2012, 11:04 AM
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.

Bart B.
November 16, 2012, 11:53 AM
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

sogarimfire
November 16, 2012, 01:35 PM
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.

Brian Pfleuger
November 16, 2012, 02:44 PM
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.

Art Eatman
November 16, 2012, 11:55 PM
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.

Bart B.
November 17, 2012, 08:30 AM
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.

JRI
November 17, 2012, 09:39 AM
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.

Bart B.
November 17, 2012, 10:01 AM
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.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.
Please explain your reasoning on this.

Art Eatman
November 17, 2012, 11:35 AM
" 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.

Bart B.
November 17, 2012, 01:41 PM
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.

Ridgerunner665
November 17, 2012, 08:24 PM
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.

Sent from my DROID RAZR using Tapatalk 2

Bart B.
November 17, 2012, 09:29 PM
I've never seen one approach the velocities I get with the 30-06 loaded to 63k psi in a modern bolt action.
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.

Art Eatman
November 17, 2012, 10:30 PM
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.

Ridgerunner665
November 18, 2012, 12:04 PM
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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Bart B.
November 18, 2012, 02:16 PM
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.

Ridgerunner665
November 18, 2012, 03:04 PM
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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Brian Pfleuger
November 18, 2012, 03:15 PM
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.


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.

Bart B.
November 18, 2012, 09:42 PM
RidgeRunner, it's relavent if you just answer the question. If you didn't measure the pressure, then you're guessing or calculating from something that probably doesn't match your stuff. All you had to do was say so.

Meanwhile, I'll easily shoot bullets faster than a SAAMI or MIL SPEC peak pressure load for a .30-06 with a 172-gr. M2 match bullet standardized at 2640 fps with a MIL-SPEC proof load for the 7.62 NATO M60 round that uses that same 172-gr bullet atop 41 grains of IMR4475 (a 5.56 NATO powder) in a standard M80 round's case and its primer. Having shot a thousand or two of these in competition from Garands (yes, they take it in stride quite handily, several service teams used them in their M14's, too) and a couple dozen through a chronograph, they clocked at 2790 to 2830 fps on average from the M1 barrel used to test them.

But wait; there's more. . .So you could put together a MIL SPEC M1 .30-06 proof load with a LC case and primer and 52 grains of IMR4198 under a 172-gr. M2 bullet then out shoot the 7.62 NATO proof load above giving that bullet near 2900 fps from your .30-06.

Note that both these proof loads produce 67,500 to 71,000 cup pressure or approaching 80,000 psi in transducer systems.

And this leap-frogging could continue until the rifle blows; just like a low numbered 1903 Springfield did decades ago when a military unit tested one to see when it would blow up; it took a case half full of Bullseye pistol powder under a 172-gr. bullet to do it.

Meanwhile, let's stick to a SAAMI pressure standards to level the playing field (shooting range?). Which means the .30-06 has about a 100 - 125 fps advantage over a .308 Win.

Para Bellum
November 21, 2012, 04:32 PM
If that matters to you as it does to me: the 308 is much less loud. Shorter case requires faster powder which causes max pressure earlier in the barrel and up to 25% less pressure at the muzzle. The target wont know the difference, your ears will over the years...

Rainbow Demon
November 21, 2012, 05:06 PM
The OAL limit of the .308 means that when bullets of over 175 gr are used the bullet must be seated deeply into the powder space reducing effective powder space.
For this reason the .30-06 is capable of handing the heavier bullets such as 200gr and heavier long range match bullets with much less pressure penalty at higher velocities.
The 1:10 twist rate of most .30-06 barrels is better suited to the longer heavier bullets than the 1:12-1:14 twist of .308 barrels.

While the original NATO ball load duplicated the original .30-06 ball, the 7.62/.308 is actually a refinement of the .300 Savage rather than a true all round replacement for the .30-06 as a sporting and long range target cartridge.

The Danes still use .30-06 rifles for their arctic circle patrols, the 06 being better medicine for polar bear than the .308.

PS
Standard commercial cartridge brass doesn't cold flow till pressures of 85,000 PSI or 68,000 CUP. Some cartridge brass can stand a good deal more.

PPS
Many low number Springfield blow ups were dure to defective subcontracted barrels. The barrels had been overheated during a bumping up process to from the shank end.
The burnt steel caused the chamber section to split breaking the receiver ring.
The same happened to an M-14 awhile back. Same cause, a defective aftermarket barrel.

The LN receivers were very hard but a bit brittle, even then almost all of the receivers that failed were from specific batches that had been overheated during the forging process.
One receiver that had held up the standard 75,000 CUP proof load and thousands of full power loads shattered like a jelly jar when a low pressure gallery/guard cartridge was fired. The low pressure did not expand the case well enough to grip the chamber walls, so the lugs took the full impact without delay.

PS
This spec sheet
http://www.everyspec.com/ARMY/TM-Tech-Manual/TM43-0001-27_CHG-2_4432/
Contains several errors that are addressed in the spec sheets for procurement of propellents.
The M118 cartridge pressures are only expressed in CUP rather than PSI
M118 special ball (and the more recent M118 Long Range) has a pressure of 52,000 CUP (with max deviation of 57,000 CUP) rather than the 50,000 PSI listed in the above linked tech manual.
M80 has pressure of 48,000 CUP/50,000 PSI.

Bart B.
November 21, 2012, 09:01 PM
Rainbow Demon's comments:The OAL limit of the .308 means that when bullets of over 175 gr are used the bullet must be seated deeply into the powder space reducing effective powder space.
For this reason the .30-06 is capable of handing the heavier bullets such as 200gr and heavier long range match bullets with much less pressure penalty at higher velocities.

The 1:10 twist rate of most .30-06 barrels is better suited to the longer heavier bullets than the 1:12-1:14 twist of .308 barrels.
Match bullets up to 250 grains have been used in .308 Win. chambers with long throats. Muzzle velocity from a 28 inch barrel's about 2150 fps. Needed a 1:8 twist to stabilize them through 1000 yards, but was very accurate when David Tubb used it in the late 1980's.

Military rifle teams shot 190-gr. Sierra HPMK's from 22 inch M14NM barrels and 24 inch M1 barrels with their standard 1:12 twist. Excellent accuracy with such loads that pushed them out at about 2450 fps for the USMC Rifle Team load of 41 grains of IMR3031 in an LC M118 primed case for their M14NM's. The USN and USAF used 44 grains of IMR4320 under the 190's in the same case and got about 2600 fps in their Garands. Both loads had peak pressures not to far from blue pill proof test loads; much higher than standard specs for the 7.62 NATO round. Both loads had the best accuracy at 1000 yards of any used in these semi autos.

When the .30-06 was "the" round for high power match rifle use, 1:11 or 1:12 twist barrels were favored for bullets from 168 to 200 grains if best accuracy was the objective.

Starting in 1963 it took only 2 to 3 years of .308 vs. .30-06 for the .308 to become the choice for matches up to 1000 yards by top classified shooters. The .308's 40% better accuracy was more advantageous than the .30-06's 10% less wind drift.

Rainbow Demon
November 22, 2012, 02:52 AM
Match bullets up to 250 grains have been used in .308 Win. chambers with long throats. Muzzle velocity from a 28 inch barrel's about 2150 fps. Needed a 1:8 twist to stabilize them through 1000 yards, but was very accurate when David Tubb used it in the late 1980's.

Would the long throat be due to seating the bullet far beyond the specified cartridge OAL?
If so the cartridge would probably not feed from the magazine of most purpose built .308 length actions or military detachable box magazines.
Some 7.62 sniper rifles are built on .30-06 length actions, but would need the throat deepened for over length loads.


Both loads had peak pressures not to far from blue pill proof test loads; much higher than standard specs for the 7.62 NATO round.
Which was what I was getting at.
A load that beats a match rifle to death in a fraction of the normal useful life is not much of a bargin unless Uncle Sugar is paying the bills.
Then again many match shooters of the thirties and earlier used hi nitro powders that destroyed the accuracy of expensive matchgrade barrels within 300 rounds, but they were willing to pay the price for a very slight edge in accuracy.

I suspect that any noticable accuracy advantage of .308 match rifles was due more to lack of interest in keeping the .30-06 competitive. The new kid on the block was getting all the development funding.
Improved low nitro double base powders may have been part of it. The .30-06 having performed better with single base powders during WW2 and before.
Double base powders tested in 06 matchgrade ammo had some of the best mean radius figures yet the next lot would have mean radius inferior to the single base powders. Single base was far more consistent from one lot to the next than available double base in those days.
Throat erosion was still a problem with double base at the time, with ten percent shorter barrel life.
The garand also operated better with the gas port pressure of single base, and there was less erosion of gas ports.
The .308 was developed from ground up to accomodate double base powders, and the M-14 was designed to handle the hotter DB ball powders by use of chrome lined bores and high temperature resistent alloy in the gas system.

The .308 with its smaller capacity would have an advantage if kept within its normal performance range, just as specialized target rounds like the 8.15X46R or .32-40 had at closer ranges. Consistency within a certain envelope outweighing maximum performance figures.
The .308 is much like the .303 British in some respects, and a number of UK shooters have told of the most accurate .308 loads being basically a balistic duplicate of .303 matchgrade loads.

With maximum ranges of 1200 yards in recent matches some have found the hotter long range .308 loads to be too much for some older match rifles, especially the converted No.4 rifles.
A few more modern .308 match rifles have also been damaged by the top end loads needed to keep the bullet super sonic at 1200 yards to avoid transition shock.

I'm no barrel maker but seems to me that the 1:10 twist developed for the 1903 .30 and the .303 when both used bullets of 215-220 grains should still be best for bullets in this range or heavier.
They did not keep the 1:10 twist because of any expectation that it would be optimal for the 150 gr .30 or the 174 gr .303, though the lightweight nose plug of the MkVII bullet meant the length was practically the same as that of the 225 gr Swift matchgrade bullet and benefitted from the tighter twist.

A bullet of 200 gr or heavier being more accurate in a 1:11-1:12 twist barrel than in a 1:10 twist is counter intuitive.
There must be more to that story than twist alone.

Bart B.
November 22, 2012, 08:54 AM
Would the (.308 Win.) long throat be due to seating the bullet far beyond the specified cartridge OAL?Yes.

If so the cartridge would probably not feed from the magazine of most purpose built .308 length actions or military detachable box magazines. Some 7.62 sniper rifles are built on .30-06 length actions, but would need the throat deepened for over length loads.The first .308 bolt action rifle was built on a standard length action with a spacer at the back of it’s .30-06 length box magazine. But the first USA made military sniper rifle was made using the Rem. 700 short action; same one their commercial version used. Best shots in the Army and Marine Corps wanted the Win. 70 action to be used as it was more reliable, stiffer and easier to maintain in the field than the Rem. 700. But Winchester was in dire financial straits at the time and Uncle Sam didn’t want to take a chance with them.

A load that beats a match rifle to death in a fraction of the normal useful life is not much of a bargin unless Uncle Sugar is paying the bills.Uncle Sugar spent zero dollars more maintaining M1 and M14NM rifles shooting those ultra hot loads. Properly built and op rods bent and fit to tight specs did not suffer. I’ve shot thousands of those loads and there were no problems.

Then again many match shooters of the thirties and earlier used hi nitro powders that destroyed the accuracy of expensive matchgrade barrels within 300 rounds, but they were willing to pay the price for a very slight edge in accuracy.Yes, and Hi Vel No. 2 was the favorite powder in the early 20th century and a good barrel for the M1903's from the DCM cost about $2.00. Those barrels lasted about 500 to 800 rounds of best accuracy.

I suspect that any noticable accuracy advantage of .308 match rifles was due more to lack of interest in keeping the .30-06 competitive. The new kid on the block was getting all the development funding.There was no development funding. When the 26-year-old “new kid on the block” using one in match rifle competition in the 1963 Nationals chambered his Hart barrel with a standard SAAMI spec reamer, it tested to sub 4" groups at 600 yards using the same powder, bullets and bore/groove specs as the .30-06. He won the Nationals with it that year. The best .30-06 match rifles of the day shot about 6 inches at 600 yards with the best bullets available. A few years later when Sierra changed over to hollow point match bullets instead of FMJBT ones, the .308's accuracy dropped to 3" or better at 600 and the ‘06 to about 5" The .308's no better now with the best bullets available and that then-new kid’s still building them today.

The difference in accuracy was the specs for the leade angles; the .308's was less and distorted bullets less as they entered the rifling. Later tests with the .30-06 with leade’s having the same 1.5 degree leade angle proved there was not any significant difference in accuracy. But the longer barrel life and milder recoil of the .308 made it easier to shoot accuratly and at a lower cost.

Improved low nitro double base powders may have been part of it. The .30-06 having performed better with single base powders during WW2 and before. Double base powders tested in 06 match grade ammo had some of the best mean radius figures yet the next lot would have mean radius inferior to the single base powders. Single base was far more consistent from one lot to the next than available double base in those days.

I’m not aware of any double base (ball) powders being tried in 30 caliber M72 match ammo. Some Winchester ball powders were used in 7.62 NATO M118 match ammo in the late 1970's and its ho-hum accuracy of even the best lots were a disappointment to competitors.
The garand also operated better with the gas port pressure of single base, and there was less erosion of gas ports.Gas port erosion was never an issue with even service grade M1 or M14 rifles. The bore wore out for service accuracy standards at 8,000 to 10,000 rounds of both. Match grade barrels were typically replaced at 4000 to 5000 rounds.

The .308 was developed from ground up to accomodate double base powders, and the M-14 was designed to handle the hotter DB ball powders by use of chrome lined bores and high temperature resistent alloy in the gas system.Peak pressure specs for both 7.62 NATO and the 30 caliber M1 round were 50,000 CUP when the 7.62 NATO hit the street. Winchester chose to spec the .308's peak pressure at 52,000 CUP, same as their .270 Win. round, as it would be used in more modern rifles like the .270 was; and SAAMI bought the idea.

The .308 with its smaller capacity would have an advantage if kept within its normal performance range, just as specialized target rounds like the 8.15X46R or .32-40 had at closer ranges. Consistency within a certain envelope outweighing maximum performance figures.There was (and still is) no difference in accuracy with the .308 with reduced loads compared to full power ones. The 300 metre international free rifle folks liked mild loads for their .308's as the milder recoil made them easier to shoot accurate. Full power loads in NRA match rifles bested out at 300 yards with equal accuracy of about 1/3 MOA in the best of them. Nothing to date's equalled what a .308 did in 1971 shooting sub 1.5 inch 10-shot groups at 600 yards.

The .308 is much like the .303 British in some respects, and a number of UK shooters have told of the most accurate .308 loads being basically a balistic duplicate of .303 matchgrade loads.Note that the Brits use a different set of objectives in their fullbore long range matches. They’ve always insisted on leveling the playing (shooting?) field by making everyone shoot the same ammo. Arsenal ammo was used and still is. Handloads are not allowed. Good lots from Great Britian’s Radway Green Arsenal shot very well even with huge muzzle velocity spreads due to compensation of the SMLE’s barrel whip making long range accuracy much better than a Mauser action based rifle.

With maximum ranges of 1200 yards in recent matches some have found the hotter long range .308 loads to be too much for some older match rifles, especially the converted No.4 rifles. A few more modern .308 match rifles have also been damaged by the top end loads needed to keep the bullet super sonic at 1200 yards to avoid transition shock.Which is why George Swenson, a British gunsmith, designed and made the Swing 4-lug single shot action in 1972. The British 7.62 NATO loads had a lower muzzle velocity spread and their SMLE’s rebarreled for that round didn’t shoot it all that accurate. That Swing action was the forerunner of more modern Paramount, RPA, Barnard, Musgrave and other single shot .308 Win. actions used in the Commonwealth’s fullbore matches. They kicked the pants off the USA 2-lug Winchester and Remington actions for accuracy with new cases from anywhere.

I'm no barrel maker but seems to me that the 1:10 twist developed for the 1903 .30 and the .303 when both used bullets of 215-220 grains should still be best for bullets in this range or heavier. They did not keep the 1:10 twist because of any expectation that it would be optimal for the 150 gr .30 or the 174 gr .303, though the lightweight nose plug of the MkVII bullet meant the length was practically the same as that of the 225 gr Swift match grade bullet and benefitted from the tighter twist. A bullet of 200 gr or heavier being more accurate in a 1:11-1:12 twist barrel than in a 1:10 twist is counter intuitive. There must be more to that story than twist alone.There is more. It’s the speed they leave the barrel at. Muzzle velocity and twist rate determine the rpm’s a bullet spins at. A given bullet weight and shape for a given caliber needs to be spun in a narrow velocity range to stabilize it well throughout its flight. Ballistic engineers at Frankfort Arsenal developing the 7.62 NATO round and the same folks at Winchester developing their .308 round knew the 150-gr. ball bullet from the .30-06 was spun too fast going out the barrel for best accuracy through 1000 yards. Harry Pope (famed barrel maker of the early 20th century) also knew a 1:10 twist was too fast for in the .30-06 Palma rifle barrels shooting 150-gr. bullets he made for the US Palma Team around 1920. They all used 1:12 twists for those barrels.

The Brits used 1:13 and 1:14 twist barrels in their fullbore long range match rifle 30 inch barrels shooting arsenal ammo’s 147-gr. FMJBT bullets. Bullets left at 2900 + fps and remained supersonic through 1000 yards. That slower rpm rate didn’t cause accuracy problems with bullets a bit unbalanced which is common in arsenal ammo. Spinning bullets too fast makes those even with a slight unbalance jump off the muzzle axis as the exit the barrel. Even today, benchresters adjust their charge weights for shorter ranges to make muzzle velocity just fast enough for the atmospehric conditions to stablize them for best accuracy at the lowest rpm rate that works. Best example's the .30BR shooting 115 to 135 grain bullets out around 3000 fps from 1:15 to 1:18 twist barrels.

shurshot
November 25, 2012, 08:43 PM
Call me a Sally, but both the 06 and 308 kick too much for my taste, at least when my .270 will drop anything I care to hunt.