So, what exactly did US military gain by switching from 30-06 to .308?

[44 AMP]

I'll try to focus...

What did the US Military gain by switching from .30-06 to .308?

They gained the cost reduction from a case 1/2" shorter.
They gained the weight reduction from the same.

They gained a size & weight reduction in the weapons for the shorter round.

What they went on to do, after gaining these advantages, would be best in another discussion.

 

[seeker_two]

The .308 makes sense as a designated marksman and machine gun round, but I don't understand why it is still used as a military sniper round. With the advent of the .300 Win Mag and the .338 Lapua, snipers can reach out a lot farther & hit a lot harder.

Then again, I never understood why we didn't adopt the 7.62x39, too....

 

[ezmiraldo]

I heard from several sources that .308 is inherently more accurate than 30-06 (although, the difference might be imperceptible). Can someone elaborate on why that is the case? It just seems odd that, although both cartridges utilize exact same bullets generally, one can be inherently more accurate than the other... I'd love to hear some thoughts on this... Is .308 inherently more accurate in particular contexts (i.e., handloading), or is it inherently more accurate across all contexts?

 

[jimbob86]

I'm not making an irrelevant point, I am making a deliberate exaggeration to illustrate my point that is totally relevant to topic. people can and do make the wrong bullet choice

By taking the elephant out of the example given, it becomes "irr-elephant".

The .308 makes sense as a designated marksman and machine gun round, but I don't understand why it is still used as a military sniper round. With the advent of the .300 Win Mag and the .338 Lapua, snipers can reach out a lot farther & hit a lot harder.

Adding yet another batch of items into a supply chain that is ....... oftentimes stretched to the raggedy edge of the 'verse, for a gain of a few inches of trajectory that is usefull in such a small amount of engagements .... bad plan.

If the situation is such that point targets regularly need to be "reached out and touched" at distances where 300WinMag would have a major advantage over the .308, why not use the .50BMG? It's already there.

Then again, I never understood why we didn't adopt the 7.62x39, too....

Weight (5.56x45 generally weighs 2/3 what the 7.62x39 does, all else being equal), NMBOS (Not Made By Our Side), x39 requires curved magazines that don't fit in our current platform are reasons that come to mind ......

 

[Jim Watson]

To the OQ, the change in cartridges made small gains in consumption of strategic materials (gunpowder and brass), a little less load on the infantryman, and somewhat better automatic weapon function. The .308/7.62 NATO was the best that could be done without giving up the long time standard caliber and ballistics.
That was important to the US command at the time. They had seen what could be done with less powerful rifles all the way back to the Spanish American War when the 7mm Mauser showed advantages over the .30-40 Krag. Surely they were aware of the various 6.5mms and the newfangled assault rifles. They had even seen that the M1 Carbine, originally intended as a sidearm substitute for officers and non-riflemen, found its way into the front lines where its light weight and 15-30 round magazines were thought to be reasonable swaps for less power. But they wanted to keep the full power "battle rifle." So they did.

I think NATO went along because they wanted an assured supply of ammo from the US in case of trouble, saving them the cost of warfighting production and inventory capacity.

 

[44 AMP]

I think NATO went along because they wanted an assured supply of ammo from the US in case of trouble, saving them the cost of warfighting production and inventory capacity

While that certainly could have figured into their thinking, I don't think it was the primary concern. Note that all the other NATO nations built their own 7.62mm NATO rifles (or bought them from a NATO nation that did) and loaded their own 7.62mm NATO ammunition, spending a fair chunk of their own change in the process.

I think it was all the OTHER things the US could provide that tipped the issue, rather than just some common ammo.

The deal that was struck was, essentially, Hi NATO! You adopt our rifle/machinegun round now, and we will adopt your pistol round (9mm) when we get around to replacing our .45s (1911A1s).

They did, and much later, we lived up to our side of the bargain, which is why the 9mm is the US military pistol round today.

 

[wogpotter]

It was more even than that! Part of the process was a universal cartridge & rifle for it, standardized throughout NATO.

Politics ruled & U.S. Army Ordinance wanted a U.S. designed & made rifle & the other choices were Belgian (the FAL), or British (The EM-2) neither of which was designed for a full power 30 caliber round.

Because they wanted to stack the odds in favor of a US product the T65 (7.62 precursor designation) was kept as a secret through years of the selection process so they could specify the requirements in such a way the U.S. design had an edge because all other entries were competing against a hidden specification they had to meet.

It had less to do with the function of the round chosen than with political control of the process involved.

Then McNamara rethought it & the 7.62 was dropped in favor of the more "cost efficient" 5.56mm. Karma a really can be a bitch sometimes!

 

[Jim Watson]

The deal that was struck was, essentially, Hi NATO! You adopt our rifle/machinegun round now, and we will adopt your pistol round (9mm) when we get around to replacing our .45s (1911A1s).

The pistol caliber agreement appears to predate the rifle caliber standardization. High Standard T3 and Inglis Lightweight BHP came out in 1948, Colt Commander in 1949, Colt T4 ca 1950, and S&W M39 late to the game in 1954 for the first rounds of competition for the 9mm US service pistol.

How long had they been working on the T65 cartridge and soliciting guns for it?


There is one school of thought that blames the 5.56 (and the 9mm) on the USAF. As one wag put it, General Lemay wanted his nuclear bombers guarded with something more modern than M1 Carbines, and the AR15 was space age enough to suit him. Of course the Army would not be outdone and bought the same.

 

[JimDandy]

The .308 makes sense as a designated marksman and machine gun round, but I don't understand why it is still used as a military sniper round

In today's military is there a difference between a specially equipped marksman and sniper? Does the military hand out .308 rifles to the good shots?

And last I heard they were putting a new platform into the sniper rifle rotation based on the 300 win-mag.

 

[wogpotter]

How long had they been working on the T65 cartridge and soliciting guns for it?

The process started in 16 Feb 1950 with the "Comparison test of United Kingdom & United States Lightweight rifles". It went forwards in fits & starts until finally being decided as the rifle M-14 (T-44) & Rifle M-15 heavy barrel (T44E1) & cartridge 7.62X51mm, 7.62 NATO. in May 1 of 1957.

 

[Ben Towe]

In today's military is there a difference between a specially equipped marksman and sniper? Does the military hand out .308 rifles to the good shots?

A designated marksman is an infantryman who carries a rifle equipped to take longer shots than the standard infantry carbine/rifle. In simple terms, he sort of fills the space between sniper and infantryman. He is there to take medium range shots that may require precision beyond what a normal soldier could be expected to achieve with standard equipment.

 

[Webleymkv]

Basically, the 7.62x51 was an attempt to have the cake and eat it too. The advantages of an intermediate-caliber rifle were shown during WWII and later in Korea with weapons like the Stg. 44 and SKS. However, many in various militaries, the U.S. military in particular, did not want to give up the long-range power and penetration of the .30-06 and other full-power battle rifle cartridges like .303 British and 7.92x57 Mauser. The 7.62x51 was the supposed solution as it offered a dimensionally smaller cartridge which would allow for lighter, more compact ammunition and a lighter, more compact gun to fire it (compared to a gun with the same features chambering one of the older, larger battle rifle cartridges) without the reduction in ballistics of true intermediate cartridges like 7.92x33 Kurz or 7.62x39 M43.

Unfortunately, while a step in the right direction, the 7.62 NATO wasn't a big enough step. Both the ammunition and the guns that fired it were still relatively large and heavy and the battle rifle ballistics came at the price of battle rifle recoil which made full-auto fire in anything smaller and lighter than a true light machine gun uncontrollable to the point of impracticality. When the first generation of NATO "assault rifles" were used in combat against true assault rifles like the AK-47, it was found that they were still unable to offset the firepower advantage of a true assault rifle.

This led to the rather hasty and poorly-executed adoption of both the 5.56x45 cartridge and the M16 rifle in order to field a true assault rifle. While both the 5.56x45 and M16 platform have both been developed into a satisfactory system over the past 50+ years, the teething problems it experienced due to being hastily adopted in the middle of a war created a stigma that still haunts both the cartridge and rifle to this day.

 

[SPEMack618]

The Squad Designated Marksman, or if you are in an unfortunate situation of being denied such luxuries down to the squad level, the Platoon Designated Marksman is generally a Soldier who has shown some level of prowess on the rifle range and sent through a quickie long range course and issued a Designated Marksman Rifle. At least that's how it was for us.

But mind you we were a National Guard Armored Cavalry Scout Troop that was told
"Hey, you guys in the funny hats, no Russian Bimps to kill, go patrol those mountain villages on foot and in hillbilly armored Humvees"

But I digress, our PDM was actually issued an M-16A3 with a really good Leupold scope atop of it. And the funny thing was, he was the kid that had never fired a rifle, not even in Boy Scouts, before OSUT.

However, other platoons in the Troop had refurbished M-14s/M-21s with scopes issued to their PDMs.

 

[44 AMP]

There is one school of thought that blames the 5.56 (and the 9mm) on the USAF. As one wag put it, General Lemay wanted his nuclear bombers guarded with something more modern than M1 Carbines, and the AR15 was space age enough to suit him. Of course the Army would not be outdone and bought the same.

That's one way to look at it. I don't think its fully correct, but it is a way to look at it.

In the version I heard, its still Lemay that's responsible, (and only for the 5.56mm, not the 9mm) but not because he wanted something "more modern". It was because he didn't have any other choice.

The Army was phasing out the M1 carbine. The Air Force got its small arms, and their support (spare parts) from the Army. With support for the carbine going away, Lemay had to find something else. He was introduced to the AR (and Stoner) and thought it would be a good gun for his airbase SP's (who, after all, don't normally get down in the mud like regular infantry).

A bit later, the MacNarama Defense Dept (whiz kids) decided that the AR & 5.56mm were the best for EVERYONE, and pushed them through as a "fully developed" weapon system, needing no further work.

Bugs/flaws did show up. Some of them were even possibly deliberately caused by those more interested in discrediting the weapon than in saving US blood. So sad.

The powers that be were determined to make the AR & 5.56mm work. Took decades to get the real flaws resolved, but they finally did it. (aside from the argument that the real flaw is the 5.56 caliber).

I believe that had the M14 been retained (in part, anyway) and given the same tinkering with, it would have wound up a much better rifle than it was when it was mothballed.

I do recall hearing about some guys who did some experimenting with the M14 gas system, reducing the cyclic rate with what was supposedly a fairly simple modification, and finding (guess what?) at a lower cyclic rate, the M14 is "controllable" in full auto fire. As far as I know, the military never even looked at that possibility.

Politics.

 

[gyvel]

Not sure if this is true or an old wive's tale, but I have heard and read more than once in the past that the .308 was "inspired" by the .300 Savage.

 

[pathdoc]

The .308 practically IS the .300 Savage, plus a few percent up in length and a substantial pressure hike.

As for the .280 British cartridge, when I read about all these new .264-.277" rounds being played around with, I thought "Someone owes the Brits a huge apology." The answer was there the whole time, and they knocked it on the head.

 

[Mike Irwin]

"How long had they been working on the T65 cartridge and soliciting guns for it?"

"Not sure if this is true or an old wive's tale, but I have heard and read more than once in the past that the .308 was "inspired" by the .300 Savage."

Investigation into what would eventually become the 7.62 round actually started before the end of World War II.

Supposedly a limited number of Garands and M1919 Browning Machine Guns were modified to chamber the .300 Savage cartridge as testbeds, and work proceeded from there.


Regarding the M16 in USAF service, I was once told, but don't know if this is true or not, that the reason the AF picked the gun is because even at close range the bullets wouldn't penetrate the casings of the nuclear weapons then in use, while at close range the .30 carbine would.

 

[Archie]

So far not mentioned...

Other than the 7.62mm rifle round (commercial .308 Winchester) being roughly half an inch shorter, the web area of the case is thicker; it therefore is more reliable in semi and fully-automatic arms as the case head is not as likely to rip off. (Not that case failure was a major problem with the .30-06.)

The M14 rifle was replaced by the M16 was - notwithstanding McNamara and the whiz kids - there were never enough M14s built and issued to fully arm the U. S. Armed Forces. When Vietnam was entered into with vigor, the U. S. was short of battle rifles. Colt - who built the M16 - was the only manufacturer who could guarantee delivery of X number of units by the expected delivery date.

Yes, General LeMay promoted the AR15/M16 rifle. It seems he was overly impressed with 'new'. After all, the aircraft were mostly 'new' designs.

Cooper did predict 'difficulties' with the next war or two. Not because of the 5.56mm rifle being adopted, but because - true to form - the people in charge were busy thinking about how to fight the last war, not the next one.

The success of the M16 in Vietnam (such as it was) revolved around the practice of using the M16 more as a sub-machine gun than as a rifle. (Area and volume fire as opposed to aimed and specific fire.)

Now in the middle east, the engagement distance are further than during the Vietnam conflict. The 5.56mm round, complete with heavier bullet, still isn't doing all that well at ranges over 100 yards or so. Closer up, in street fighting or house clearing, it's doing as well as ever. Especially when shooting an adversary several times in rapid succession.

Was adopting the M16 a mistake? Probably not a mistake as much as desperation and "... seemed like a good idea at the time." I carried one for a while, qualified with one and never was impressed with the silly thing, over all.

Except when carrying it on forced marches.

 

[Slamfire]

How long had they been working on the T65 cartridge and soliciting guns for it?

This is from page 49 of the Oct 1973 American Rifleman. Sometimes keeping these old magazines is better than tossing them out!

History of T65 Cartridge


The preliminary drawing for the experimental cal 30 short cartridge was completed at Frankford Arsenal on Dec 12 1944, under the nomenclature Cartridge Ball, Cal. 30, T65. The T designation indicated a test items. The preliminary load development work was done at Aberdeen Proving Ground early in 1945.

On March 6, 1945, Frankford Arsenal was directed to produce 15,000 T65 cartridges for experimental test barrel firing. Manufacture of this ammunition, using IMR propellant, was completed in August 1945. This loading gave an average instrumental velocity of 2600 fps at 78 ft from the muzzle.

After the initial production by Frankford Arsenal, development of the T65 cartridge continued with the assistance of Olin Mathieson chemical Corp and Remington Arms Co. On Dec 15 1953, the final form of the T65 cartridge, the T65E3, was adopted as the 7.62 mm NATO by the North Atlantic Treaty Organization nations of Belgium, Canada, France, United Kingdom, and the United States. Formal standardization of this round as a U.S. rifle-caliber military cartridge occurred in August 1954.

Given that the development was during WW2, I cannot see how there would have been any support for a midpower round at the time.

I think the abandonment of the 276 Pedersen was the wrong decision at the wrong time. Just as the adoption of the 7.62 Nato was the wrong cartridge at the wrong time.

We should have just copied the 7.5 X 55 Swiss in 1903 instead of coming up with a new round. The Swiss case was shorter, has a very thick rim, and was an outstanding round. If we had copied it, we would not have had to change over to a shorter round, the 7.62 Nato, for machine guns.

 

[Jim Watson]

We should have just copied the 7.5 X 55 Swiss in 1903 instead of coming up with a new round.

Or we could have bought the whole 98 Mauser package instead of picking and choosing design features to carry over into the 1903. But I don't think a .30x2 1/4" (7.62x57 back in Oberndorf) would have had any different career other than to have carried over into post Garand rifles instead of being marginally improved as with .30-06 to .308. We would still have entered the assault rifle era after seeing German and Soviet weapons.

If we had then wanted to stick with the .30 instead of going with the 7 and 8mm Euroguns or a varmint rifle, it could have been done. Look at the 30x1.5 in CotW.