308 vs 30-06 and other rounds? WHY is a 308 better?!?

[WildRose]

The cartridge, bullets and rifles don't know what they're being used for. They perform the same way in any shooting discipline.

But then the same rifles rarely are used for both hunting and competition.

Then why did the US Army Advanced Marksmanship Unit recently pick the .308 cartridge for the new service rifle they chose to out perform the .223 Rem. and 5.56 NATO in long range competition? If the '06 really was superior with all the modern powders, bullets, primers and cases, they would have picked it.

They chose the .308 for the same reasons we chose the 308 forty years ago. Nearly identical performance out of short action with far lower weigh for the same volume of ammo. They also shoot highly modified/accurized versions of existing service rifles and there is no 30-06 service rifle still in the inventory.

.308 bullets driven by any popular case is always going to be superior to the 5.56 at long range due to the higher BC bullets.

 

[Coalforge]

Well, I got here on a search as a friend has a rifle in each caliber that were his Dad's. He is going to bring them both over tomorrow and let me shoot a couple boxes of ammo through them. I will make the choice depending on which weapon feels best to me and not worry about the caliber. Thanks for all the input.gun)

 

[Coalforge]

Well, I got here on a search as a friend has a rifle in each caliber that were his Dad's. He is going to bring them both over tomorrow and let me shoot a couple boxes of ammo through them. I will make the choice depending on which weapon feels best to me and not worry about the caliber. Thanks for all the input.gun)

 

[Bart B]

In response to:
Why did the US Army Advanced Marksmanship Unit recently pick the .308 cartridge for the new service rifle they chose to out perform the .223 Rem. and 5.56 NATO in long range competition? If the '06 really was superior with all the modern powders, bullets, primers and cases, they would have picked it.

They chose the .308 for the same reasons we chose the 308 forty years ago. Nearly identical performance out of short action with far lower weigh for the same volume of ammo. They also shoot highly modified/accurized versions of existing service rifles and there is no 30-06 service rifle still in the inventory.

The Army wanted the best available semiauto .308 rifle to out perform the ones shooting 22 caliber bullets. If they had M14NM's available, they would have easily competed head to head with the 7.62 NATO Garands that were outperforming the 5.56 rifles at 1000 yards. They picked the AR10 because it was already available and did what they wanted it to do with the .308 round. But to get it allowed in NRA matches, the Army had to get the NRA to write a rule in the High Power Rule Book allowing AR10's to be a "Service Rifle" like M1, M14, M1A, M16 and AR15 rifles are; the NRA put it in the rule book. With hot loads with Berger 185 VLD's they did very well setting the record for service rifles in the long range team match at the Nationals last year. They did not want a .30-06 in any way.

 

[luke]

I have enjoyed reading all of the replys. Some of my buddies have 30-06 while myself and another buddy have 308'. I reload for all and have shot both reloads and factory through the chrono. 2 of the 06' are factory guns ( 1 a browning a bolt and the other a vanguard) both 308' are factory savage. My 308 with a 168 gr will shoot 25-60 fps faster than either 06 no matter the ammo. Both 308' shoot 155gr faster than both 06 and both 06 will shoot a 168 faster than my buddies 308. We have never used any heavier bullets so I can not say which would be better. As for one cartridge being better then the other is really in the eye of the beholder. In my experience with them they are side by side ballisticly. But my 308 is alot more forgiving on the shoulder at the end of the day.

 

[Bart B]

In comparing the .30-06's case capacity's about 20% more than the .308 and its powder charges are about 15% more than the .308's, there's no way a .308 Win. will shoot a given bullet of of a barrel whose bore is dimensionally equal to one chambered for the .30-06 when both produce their standard peak pressures.

However, a souped up .308's charge will certainly shoot a given bullet faster than a tamed down .30-06 load.

And a tight bore .308 barrel will usually shoot SAAMI spec .308 ammo's bullets out faster than a loose bore .30-06 shooting SAAMI spec ammo's bullets.

Luke, I'd like to know the load, dimensional and pressure differences between that .308's stuff that shoots the same bullet faster than the .30-06 stuff does. If you know them, please share them with us.

 

[liltank]

Luke, I'd like to know the load, dimensional and pressure differences between that .308's stuff that shoots the same bullet faster than the .30-06 stuff does. If you know them, please share them with us.

That's what I was thinking as well. Sounds to me like you have a low powder charge in the 06' for accuracy and happen to find a high speed load suitable for your .308.

 

[luke]

In my 308 I use 43gr of imr 8208xbr with a win mag primer and a 168gr amax. With a 155gr amax I use 47gr of varget and a cci large rifle primer. That is for both 308. With no pressure signs. The a bolt 30-06 uses a 155gr amax with 54gr of blc-2 and a win mag primer. The weatherby vangaurd uses a 168gr sierra gameking with 57.5gr imr 4350 and a cci large rifle primer. All guns have 24inch barrels except my 308 which had a 26. All 4 rifles were shot through the same chrono by the same guy within minutes of each other. I agree that with more case capacity the 06 should shoot a little faster but that is not the case with these particular rifles.

 

[Bart B]

I agree that with more case capacity the 06 should shoot a little faster but that is not the case with these particular rifles.

I don't think it's the rifles that make that difference. It's the loads. Without accurate pressure data (numbers and curve shapes) for all the loads used, the comparison's not valid in my opinion.

Visible changes one sees in cases and primers are the least accurate way to measure pressure. There's no metalurgy standards that every case and primer cup maker follows to the letter. It's a rubber ruler.

Having fired hundreds of 7.62 NATO "proof" loads at about 65,000 CUP and the cases look no different than standard loads with the same case, primer and powder charge producing 50,000 CUP fired in the same barrel, that pretty much shows what a 15,000 CUP difference can show in cartridge appearance. The difference between loads was 172-gr. FMJBT bullets were used in the proof loads and 147-gr. FMJBT bullets used in the standard load.

 

[Tnwhip]

I read a book a while back about a Marine Sniper in Vietnam. He was shooting the Model 70 30-06. When they took it away and gave him the Rem 700 in 308 he didn't like it because he lost 200 yards. He never said anything about one being more accurate. He just just didn't have the range he did with the 30-06. I can see why they changed from 30-06 to 308 to 223. We could carry more ammo. But for snipping I can't see why they would want to short change them? Hathcock won Camp Perry with a 300 Mag. Why didn't they let all the snippers use the 300 mag back then? Don't make sense. At least now our snippers have the guns they need.

 

[Bart B]

I doubt Gunny Hathcock lost 200 yards in range going from the .30-06 M72 round to the 7.62 NATO M118 rounds. Both rounds used in Viet Nam used 172-gr. FMJBT match bullets. The difference in range where the .30-06 bullet's moving 1222 fps at 1000 yards and the same bullet from the NATO round's only about 50 yards; it's moving at 1222 fps at 950 yards.

While the Gunny may have said that, in 1971 at the Interservice Rifle Matches he told me he liked his old, near shot out .30-06 because he knew very well the trigger's feel and letoff as well as the round's adjustments for different ranges and wind with bullets coming from it in the lot of ammo he used. He didn't like the Rem. 700's triggers at all. When the USMC unit at Quantico tested his rifle after he retired, it shot his lot of match ammo into about 18 or more inches at 1000 yards; the barrel was somewhat eroded in its throat. The Rem 700's in 7.62 NATO shot about 10 inches at 1000 with a good lot of M118 match ammo according to the USMC rifle team members I talked with back then about their new sniper rifle.

In the late '60's the USN Match Conditioning Unit in San Diego came up with a round for a sniping cartidge. A .30-.338 Win. Mag. with its belt and rim turned down to body diameter and a new extractor groove cut. Called the .30 Super, it had the same great 1/2 MOA accuracy at 1000 yards as its parent case but without all the accuracy headaches of the belt. The other services were shooting .30-.338's in long range matches winning and setting records, but the powers to be said no, they'd use the 7.62 NATO match round.

 

[Tnwhip]

I doubt Gunny Hathcock lost 200 yards in range going from the .30-06 M72 round to the 7.62 NATO M118 rounds. Both rounds used in Viet Nam used 172-gr. FMJBT match bullets. The difference in range where the .30-06 bullet's moving 1222 fps at 1000 yards and the same bullet from the NATO round's only about 50 yards; it's moving at 1222 fps at 950 yards.

While the Gunny may have said that, in 1971 at the Interservice Rifle Matches he told me he liked his old, near shot out .30-06 because he knew very well the trigger's feel and letoff as well as the round's adjustments for different ranges and wind with bullets coming from it in the lot of ammo he used. He didn't like the Rem. 700's triggers at all. When the USMC unit at Quantico tested his rifle after he retired, it shot his lot of match ammo into about 18 or more inches at 1000 yards; the barrel was somewhat eroded in its throat. The Rem 700's in 7.62 NATO shot about 10 inches at 1000 with a good lot of M118 match ammo according to the USMC rifle team members I talked with back then about their new sniper rifle.

In the late '60's the USN Match Conditioning Unit in San Diego came up with a round for a sniping cartidge. A .30-.338 Win. Mag. with its belt and rim turned down to body diameter and a new extractor groove cut. Called the .30 Super, it had the same great 1/2 MOA accuracy at 1000 yards as its parent case but without all the accuracy headaches of the belt. The other services were shooting .30-.338's in long range matches winning and setting records, but the powers to be said no, they'd use the 7.62 NATO match round.

It was not Hathcock That said said he lost 200 yards. I was reading about another Marine snipper I don't remember his name but I think the name of the book was Dead Center. This guy was saying he didn't like the 308 because he lost some range . That is all I know.

 

[Michael Eichele]

There's no doubt that at max potential for each the 30-06 will have higher velocities. That being the case, the 308 today, with modern powders and such, can far out perform what the 30-06 could do 25 years ago. With the insane accuracy, consistency, high BC projectiles and higher velocities than ever before, the 308 is a serious LR round. Be it match, hunting or sniping. With the excellent modern day capabilities, my opinion is that if you make the switch to a long action, make it worth your while. Go for a 300 win.

25 years ago with the bullets and powders available it took the large magnums to hit the 1000' pound mark at 1000 yards. Now there are 308 loads that hit with 1000 pounds at 1000 yards. Granted, this is the upper limits but illustrates how far we've come with bullet design and velocities.

My current primary 308 is a true SAMMI spec rifle. It shoots federal gold medal match ammo right at 2600'sec. Right where it's suppose to. I have no interest in pushing hot hand loads through it. My hunting 308 has fired 168 amax's @ 2950fps with double base powders and a 26" barrel with 1/4 MOA accuracy and zilch for pressure signs. even using cheap cases. It's also peaked over 2700 with the 200smk. 25 years ago this was a pipe dream for either of these cartridges. I decided it seemed morally wrong to push the 168s to 2950 so I settled on 2833fps as my go to load for that weight. Still higher that thought possible back then.

 

[Bart B]

It was not Hathcock That said said he lost 200 yards. I was reading about another Marine snipper I don't remember his name but I think the name of the book was Dead Center. This guy was saying he didn't like the 308 because he lost some range . That is all I know.

"Dead Center" was Ed Kugler's account of his two years as a Marine scout-sniper in Vietnam.

I've known a few snipers on USN SEAL teams and most of them are a bit ignorant (not stupid nor dumb) about down range ballistics. A former SEAL Team Commander I used to shoot matches with feels the same way about them as well as other service branch snipers, but they're sneaky guys and good shots in spite of all their technical shortcommings.