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Old January 29, 2014, 04:08 PM   #51
Bart B.
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David, if one checks the details of how the .308 became the favorite competition cartridge over the .30-06 from late 1963 through the next few years, here's what they'll observe. And the difference was microscopic. The first .308 chambered rifles that outscored the .30-06 ones were identical except for their chambers. They even used the same components except for the case.

The first bolt action rifles were Win 70 receivers originally made for .30-06 size cartridges but with a spacer at the back of the magazine and a longer bolt stop so the bolt throw would be about half an inch shorter. Barrels in competition were typical 26" long ones tapering from 1.2" at the breech to .900" at the muzzle. Hart made most of them and they all had the same bore and groove diameters that worked best with Sierra's bullets. Both had 1:11 twists. A few people tried using the Rem. 700 short action but it had too many faults to make any realistic comparison between short and long actions with .308 barrels in them. As it turned out, those round ones didn't hold bedding as good as the flat bottom/sides Win 70's did and, along with magazine feed, trigger and extractor problems, the 700's were not popular.

The semiauto version was the M1 with the difference between the old .30-06 parts list, a 7.62 chambered barrel made by Springfield Armory in MA with a slightly larger gas port and a 1:12 twist. It took the M14 shops an extra year or so to work out the details of making them shoot as accurate as the 7.62 Garands, but they finally did it. Both shot more accurate with aftermarket match barrels; almost as accurate as what bolt guns did.

Both the 7.62 NATO and .30-06 peak pressure specs as measured by arsenal copper units of pressure systems were identical; 50,000 cup. What Winchester used for their .308 Win cartridge was a different cup system and therefore had different numbers emerge from it. Otherwise, both cartridges operated at the same peak pressure.

Someone told me years ago that Remington went to 1:10 twists for their .308 chambered barrels because most customers thought that was the best for heavier bullets. Didn't matter that Winchester used 1:12 with great success even with 200-gr. round nose bullets. That does make it cheaper to use the same mandrel for hammer forging the same 1:10 twist 30 caliber barrels for all sorts of cartridges.
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Last edited by Bart B.; January 29, 2014 at 04:18 PM.
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Old January 29, 2014, 07:03 PM   #52
DAVID NANCARROW
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Bart, if you will pay closer attention to my post, I mentioned that a lot of the commercial rifles used a 1:12 twist in their 308 chambering. Nothing mentioned about Hart barrels or specialty target rifles. If you care to look at Big Green's current offerings in 308, you will find that more than half of them still give the 1:12 twist barrel to the 308.
I notice that Savage tends to lean toward the 10 twist, but I really don't know when this began with that firm.
Winchester seems to offer the M70 in 308 with a 1:12 twist only.

Not so sure what special CUP rating the 30-06 used to use, but SAAMI spec shows in PSI that the 06 max average pressure is 60K while the 308 is 62K. I chalk that up to some of the older rifles chambered in 06 as compared to the newer steel alloys available in the 1950s
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Old January 30, 2014, 11:13 AM   #53
Bart B.
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David, I noticed what you're reminding me of. My post was put up to explain what detailed and valid reasons were behind the .308's better accuracy than .30-06's when it's preference for accurate cartridges originated.

There's lots of info on the 'net stating the arsenal pressure systems used on military small arms ammo set both the .30-06 and 7.62 NATO round at 50,000 cup. That's still the SAAMI spec for the .30-06, but Winchester's different sytem details for CUP measurements for their .308 Win case were established at 52,000 cup as easily seen on pages 15 and 16 in:

http://www.saami.org/specifications_...wnload/206.pdf

Read post 4 in the following:

http://www.xcrforum.com/forum/19-308...62-x-51mm.html
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Old January 31, 2014, 06:04 AM   #54
DAVID NANCARROW
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Agregory, I have no personal experience with the scope your package comes with, but I do have some with the Howa in 30-06. It seems to be a pretty decent, reliable action. They also have a good reputation for accuracy. Feed it decent ammunition and do your part, and I believe you wont be disappointed!
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Old Yesterday, 09:25 AM   #55
greggy99712
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30-06

I;m shooting a remington 700, berger 168's and hitting 1/2 moa at 800 yds. I'll keep my 'o6 thank you
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Old Yesterday, 10:40 AM   #56
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Quote:
instead of ordering the same gun in .308 for $200 more.
If you are being charged $200 more for the same gun in .308, you are being ripped off, and a fool if you pay it.

From the OP, you are looking at a $450 gun? rifle & scope combination? Sadly, in today's market, that makes it a bargain gun, and while perfectly serviceable for many things, they are never the highest quality, and so not suited for highly specialized things (like long range match shooting).

To make an imperfect analogy, go buy a new Ford economy car (Fusion?), or something similar. Perfectly fine for getting around town or taking a trip, but you won't see any running at Daytona...

The accuracy advantage of the .308 over the .30-06 exists, but its only significant in match rifles and long range shooting. in the field, it is essentially meaningless.

Also the 100fps difference between the two means approximately half an inch difference in drop at 100yds (and the ratio is constant as the distance increases). There is no animal that can tell the difference, and for every guy who thinks the 06 drops 'em faster or kills them deader, there is a guy who thinks the .308 does it better than the 06.

When you are talking about regular sporting rifles any individual rifle (and ammo) in 06 may be more accurate than another individual one in .308, and the opposite is also true.

Quote:
Remember one of the reasons the military went from 30-06 was because to a certain extent it was it was an over-kill ON HUMANS!
This sounds sensible, except that the military replaced the 06 with a round that had EXACTLY THE SAME BALLISTICS! There is a whole 10fps (TEN FEET PER SECOND) difference in the specs for GI ball .30-06 and .308 (150gr bullet). There is NO DIFFERENCE between the two.

Where you get the 100fps (200fps maybe, with certain loads) is shooting commercial ammo in civilian rifles.
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Old Today, 12:47 AM   #57
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Gentlemen, an informative read, thank you.
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