Long Range Precision - When Why and How .308?

Redhouse

Redhouse

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Serious question, not a troll or tryna start a debate or flamefest. Just a general curiosity question. .223 and .308 seem to be the defacto standards for long range precision. And yes, I know there are other choices with some popularity, like .300WM, .338L, and so forth. I'm just curious why .308 became a standard as opposed to, say, .30-06 which shoots flatter. Did it have to do with cartridge development, or....??? Is it as simple as flat out long term accuracy?

I know parts and pieces would be harder to come buy but would a long range precision piece in .270 or .270WSM or .30-06 be viable?

Cheers. :wave:
 
I would not say these rounds are the paradigms of long range precision, not any more anyway, though they have produced great results. Their popularity is probably due to their background as military cartridges with all its research and development - and the evolution into Palma shooting. 30-06 is - in military terms - obsolete. 308 is still used esxtensively in sniper weapons systems.
 
308 is the standard NATO rd for sniping. All the information gathered about the round and the number of bullets, cases, and powder choices have made it very appealing to use. Why reinvent the wheel if it is already there?
 
target Rifle

all these shooters Friday where shooting .308win max weight of bullet 156gr in the Canadian open shoothttp://
The shoot starts Monday for the world championships many country's participating again all .308win
 
I wanted to get into long range precision shooting, but I also want to learn how to hunt...after thinking about it for a long time, I ended up ordering a Savage .30-06. I realize that as I get into it more, I'll most likely want a better target rifle in a different caliber, but at least I'll have a good hunting rifle and it'll buy me some more time to get a better target setup.
 
308 is very tolerant of different powders and bullet weights. It's also easier to shoot than 30-06 etc, and practice is what makes those shooters so good.

For smaller bores, I think 223 is way down the list for high end competition, but is popular among many because it's cheap, ubiquitous in ammo availability and rifles, and also a great varminting round.
 
In Canada, the 223 will run right next to the 308 in LR classes where these cals are the only ones allowed. New bullets have made the 223 a very viable shooter. Shooting out to 1000m, I can say from experience it gives up little if any to the 308.

The 80gr Amax will equal the 155gr 308 loads. yes, there is an ongoing debate about heavier bullets bouncing less in the wind. Maybe true but it takes too level shooters to make either cartridge work effortlessly.

For pure LR ballistics, the 223 and 308 are now ballistics dogs. They simply cannot compete with the 6mm, 6.5's and 7's.

Like push rod V8's in Stock car, the 308 continues to be popular despite enormous improvements in tech because there are several international classes set up specifically for this cartridge.

6mmbr.com will give you an enormous amount of info on all manner of LR shooting. F class is becoming the number one LR shooting sport around the world. They class the 223/308 together in F(F) and everything else is in F(O).

Tells you something.

Jerry
 
Silverado said:
308 is very tolerant of different powders and bullet weights. It's also easier to shoot than 30-06 etc, and practice is what makes those shooters so good.

My feelings exactly. Consistent loads of any powder of generally correct burning rate, using good bullets and the rifle will shoot to its potential. Way less frustration than I've had with some cartridges.
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Current long range (1000yds & over) benchrest results are won by the large .30 magnums more often than any other. The smaller calibers in the hands of experienced competitors do win but not with the regularity of the big 30's.

Managing recoil is a major limiting factor in rifle competitions. Whether they admit it or not all shooters are distracted by it - some more than others. In the unlimited class benchrest 1000yd matches the big .30's manage recoil in rifles weighing 50 to over 100lbs and may be equipped with muzzle brakes where allowed - and they win more than any other caliber.

It is possible that the .338 Magnums could displace the .30's if recoil could be managed and a better selection of match grade bullets were available. Neither of these things are likely to happen so the .30 Magnums should remain on top for some time.

The short benchrest competitions and the other non-benchrest longer range competitions will continue to be dominated by the various 6mm to 7mm cartridges but where it is practical to manage recoil with weight & muzzle brakes the big .30's are king - the recorded 1000yd benchrest results say so.

The .223 Remington and .308 Winchester are great calibers and compete well within their class but ultimate long range accuracy is not their game.
 
Redhouse

Regarding your question about the viability of the .270. It has two fatal flaws:( - the very limited availability of match grade barrels & bullets.
 
Thanks to mystic and gunster; great posts!

One thing that so many don't realize is that 'flat shooting' cartridges don't give any advantage whatsoever, simply by virtue of a flat trajectory curve. As I've said before, you can dial clicks all day long if you know your load.

Where FASTER loads do give a benefit is in a SHORTER FLIGHT TIME, which equals less time for wind to act on the path of the bullet. It's a distinction not recognized by many IMO.

Of course, those who are actually competitive in LR may correct me if I'm wrong...
 
Silverado said:
Where FASTER loads do give a benefit is in a SHORTER FLIGHT TIME, which equals less time for wind to act on the path of the bullet. It's a distinction not recognized by many IMO.
QUOTE]

While there is merit to choosing a high velocity cartridge or load to reduce flight time at intermediate ranges, at long range the lower muzzle velocities resulting from heavy for caliber bullets loaded with smaller powder charges have certain advantages. Smaller powder charges often result in a lower extreme velocity spread resulting in tighter groups at the target. According to my ballistic software, an extreme spread of mere 25 fps with a 155 gr Sierra (2900 fps compared to 2925 fps) moves the POI 7". As for drift if we compare two .308 loads - the Sierra 155 gr MK at 2900 and the 200 gr MK at 2500, in a 10 mph cross wind the 200 gr MK has 8 minutes of drift compared 9 minutes for the 155, so a real world advantage of one over the other is almost nill.

Choosing cartridges with smaller powder charges makes shooting over the season less expensive in two ways. The most obvious is that powder consumption is lower, but the smaller powder charge is also less wearing on barrels. A rule of thumb I came across years ago is that in medium bores say from 6.5 to .375, the rounds which produce the longest barrel life are those with powder charges not exceeding 1/3 of the bullet weight. This does not seem to apply to small bores as .22's with powder charges of up to 35 grs do quite well. In big bores it is not an issue because powder charges are much lighter in relationship to bullet weight - at least in hand held rifles. It is interesting to note however that the .50 BMG falls with this rule. As an extreme example, it's not hard to see that a .308 will be less expensive to shoot than a .30-378, and within the .308's super sonic range of 1000 yards or so, it might be more accurate.
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http://www.dcra.ca/CFRC Rules/RuleBook.htm

11.05 Rifles
...
(3) TR Competition Rifles

...
(iii) Calibre and Chamber. 7.62mm (or the nominally equivalent trade designation .308 Winchester) or 5.56mm (or the nominally equivalent trade designation .223 Remington). Both designations refer to the calibre and chamber only and in no way to the type or model of ammunition. In particular, TR rifles must not exceed the maximum, applicable SAAMI or CIP chamber specifications, and "improved" chambers are explicitly prohibited for either calibre.
 
shazam*:

It's interesting that the rule you quoted gives 7.62mm and .308 Winchester. By 7.62, I take it to mean any .30 cal including 7.62 x 39, 7.62 x 51, 7.62 x 54, .308, .30-06, etc. etc. But, when they add "normally equivalent designation .308 Winchester", does that effectively exclude all other .30 caliber except the .308 (7.62 x 51)? Why would they just say "7.62mm" then?

Cheers.
 
Beyond 500yds, the issue is more about wind drift then bullet speed.

All bullets slow down when the leave the muzzle. High BC (long pointy aero bullets) slow down less so although they usually start off a bit slower, they end up going faster because of reduced drag.

Just look at a 40gr Vmax out of a 22/250 (3900fps) vs a 139gr Lapua 6.5mm going 2900fps at 1000yds. compare wind drifts and drop.

That is what reduces overall time of flight AND wind drift. Both very important.

Ideally, you would have both high BC AND high velocity. Small cals like the 6 and 6.5 accomplish this without beating up the shooter. The larger bores offer bullets of better aero but unless you can shoot mondo cases or handle the recoil, scores don't improve - likely fall.

In shooting classes that do not limit you to the 223/308, it is a balancing act between the task of the sport, number of rds, distance, recoil management due to rifle restrictions.

What you will see is a trend towards a set of components ideal for a given sport. That may change as new components are introduced.

We have never had so many excellent and accurate options. Almost everything 'cutting edge' is also available off the shelf without huge cost premiums. That is great for the sport.

Shooting is the one of the few equipment intensive sports where anyone can afford "F1 level" of technology.

Allstone, 7.62 refers to 7.62NATO which defines the cartridge quite nicely.

Jerry
 
Boomer, regarding your quote "As an extreme example, it's not hard to see that a .308 will be less expensive to shoot than a .30-378, and within the .308's super sonic range of 1000 yards or so, it might be more accurate."

The .308 Winchester's super sonic range is a bit more than 1000 yards but in real life unlimited class benchrest competitions it does not win at that distance. Much higher speeds of the big .30's combined with the better ballistic coefficient of a long and heavy 220/240gr VLD bullet trumps the .308 Win. every time.
 
Allstone said:
shazam*:

It's interesting that the rule you quoted gives 7.62mm and .308 Winchester. By 7.62, I take it to mean any .30 cal including 7.62 x 39, 7.62 x 51, 7.62 x 54, .308, .30-06, etc. etc. But, when they add "normally equivalent designation .308 Winchester", does that effectively exclude all other .30 caliber except the .308 (7.62 x 51)? Why would they just say "7.62mm" then?

Cheers.
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Because to the military, when they say 7.62, they mean 308. - dan
 
Mysticplayer said it all very very well, I got into long range shooting in a small way this tear at Connaught in Ottawa using a off the shelf Rem 700 Police in .223 very pleasant to shoot but having a hard time getting a load with the 75gr bullets to shoot past 500 yards.
Watch a a American shooter I think his name is Warner using a Win 7mmwsm in a F/O class he was hitting V bulls with ease at 900 meters he won everything.
But i talked with a fellow who shot with him in a big shoot in USA this summer, his first day he was by far trhe best shooter, 2nd day others where keeping up to him, third day he faded and last day was a bust, his shoulder was black and blue right down his arm. and this is a 22lb class gun.
How can people say the big 30, will dominante this type of shooting the recoil becomes a major factor
 
I don't shoot competitively and I only give passing attention to the results of the long range shoots, but it seems to me that most of the winners of 1000 yard matches these days are shooting some sort of 6mm wildcat. For those who wish to experiment at ranges beyond 1000, the big .30's take a back seat to the .338 Lapua, .408 Cheytac, and the .50 BMG. All of these cartridges, as well as the big .30's present a recoil and blast problem that will limit shooter endurance as stated by Manitou210 above. Having said that a fellow in Colorado made hits on a 16" gong at 3000 yards (3120 if I recall) with a .308 AI loaded with 220 gr MK's @ 2400.

Speaking of extreme long range shooting with a .308, I am still impatiently waiting for the new aluminum tipped .308/215 gr bullets from Wildcat. Has anyone shot these yet, or got delivery of them?
 
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